Value of variable in my user control keeps getting reset

Collapse
This topic is closed.
X
X
Collapse
 
  • Page of 1
  • Time
  • Show
Clear All
new posts
Previous template Next
  • Nathan Sokalski
    #1

    Value of variable in my user control keeps getting reset

    I have a user control that contains three variables which are accessed through public properties. They are declared immediately below the "Web Form Designer Generated Code" section. Every time an event is fired by one of the controls contained in the User Control, these variable are reset. Here is my current code (I have a little more to add later, right now I am just concerned about the variables getting reset):


    Public Class DatePicker2
    Inherits System.Web.UI.U serControl

    #Region " Web Form Designer Generated Code "
    'This call is required by the Web Form Designer.
    <System.Diagnos tics.DebuggerSt epThrough()> Private Sub InitializeCompo nent()
    End Sub
    Protected WithEvents ddlMonth As System.Web.UI.W ebControls.Drop DownList
    Protected WithEvents ddlDate As System.Web.UI.W ebControls.Drop DownList
    Protected WithEvents ddlYear As System.Web.UI.W ebControls.Drop DownList
    'NOTE: The following placeholder declaration is required by the Web Form Designer.
    'Do not delete or move it.
    Private designerPlaceho lderDeclaration As System.Object
    Private Sub Page_Init(ByVal sender As System.Object, ByVal e As System.EventArg s) Handles MyBase.Init
    'CODEGEN: This method call is required by the Web Form Designer
    'Do not modify it using the code editor.
    InitializeCompo nent()
    End Sub
    #End Region

    Private datevalue As Date = Date.Today
    Private startyear As Integer = 1900
    Private stopyear As Integer = 2100

    Public Property SelectedDate() As Date
    Get
    Return Me.datevalue
    End Get
    Set(ByVal Value As Date)
    Me.datevalue = Value
    Me.CreateLists( )
    End Set
    End Property
    Public Property FirstYear() As Integer
    Get
    Return Me.startyear
    End Get
    Set(ByVal Value As Integer)
    Me.startyear = Value
    End Set
    End Property
    Public Property LastYear() As Integer
    Get
    Return Me.stopyear
    End Get
    Set(ByVal Value As Integer)
    Me.stopyear = Value
    End Set
    End Property

    Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArg s) Handles MyBase.Load
    Me.CreateLists( )
    End Sub

    Private Sub CreateLists()
    'Date is currently set at this point
    ddlMonth.Items. Clear()
    ddlYear.Items.C lear()
    ddlDate.Items.C lear()
    For i As Integer = 1 To 12
    ddlMonth.Items. Add(New ListItem(System .Globalization. DateTimeFormatI nfo.CurrentInfo .GetMonthName(i ), CStr(i)))
    Next
    For j As Integer = Me.startyear To Me.stopyear
    ddlYear.Items.A dd(CStr(j))
    Next
    For i As Integer = 1 To Date.DaysInMont h(Me.datevalue. Year, Me.datevalue.Mo nth)
    ddlDate.Items.A dd(New ListItem(CStr(i ) & " " & System.Globaliz ation.DateTimeF ormatInfo.Curre ntInfo.DayNames (New Date(Me.dateval ue.Year, Me.datevalue.Mo nth, i).DayOfWeek), CStr(i)))
    Next
    ddlMonth.Select edIndex = Me.datevalue.Mo nth - 1
    ddlYear.Selecte dIndex = Me.datevalue.Ye ar - Me.startyear
    ddlDate.Selecte dIndex = Me.datevalue.Da y - 1
    End Sub
    End Class


    <%@ Control Language="vb" AutoEventWireup ="false" Codebehind="Dat ePicker2.ascx.v b" Inherits="WebAp plication1.Date Picker2" TargetSchema="h ttp://schemas.microso ft.com/intellisense/ie5" %>
    <asp:dropdownli st id="ddlMonth" runat="server" AutoPostBack="T rue"></asp:dropdownlis t>
    <asp:dropdownli st id="ddlDate" runat="server" AutoPostBack="T rue"></asp:dropdownlis t>
    <asp:dropdownli st id="ddlYear" runat="server" AutoPostBack="T rue"></asp:dropdownlis t>


    Thank you in advance for your help.
    --
    Nathan Sokalski
    njsokalski@hotm ail.com
    有声小说网-无弹窗小说阅读网
    http://www.nathansokalski.com/
    有声小说网为广大读者提供热门小说在线免费阅读，本站收集的网络文学小说情节跌宕起伏，有声小说网是值得书友们收藏的小说在线阅读网。

    Tags: None
    • S. Justin Gengo
      #2
      Re: Value of variable in my user control keeps getting reset

      Nathan,

      All page objects are closed/disposed of after the page is sent to the client.

      What this means is that your page is being recreated each time the client connects to it. Your variables are set up in such a way that they are recreated each post back that is why they are reset.

      Whenever you change the variables you're going to need to store their new values somewhere that will persist between the page being sent to the client and then destroyed on the server so you can get the original values back. In this case I would store the values in viewstate and retrieve them on postback.

      For example you could store the width of a control in viewstate like this:

      ' Declare the Width property.
      Public Property Width() As String
      Get
      Return CType(ViewState ("Width"), String)
      End Get
      Set
      ViewState("Widt h") = value
      End Set
      End Property



      --
      Sincerely,

      S. Justin Gengo, MCP
      Web Developer / Programmer

      Attention Required! | Cloudflare
      https://www.aboutfortunate.com


      "Out of chaos comes order."
      Nietzsche
      "Nathan Sokalski" <njsokalski@hot mail.com> wrote in message news:uBRGb3WxFH A.4032@TK2MSFTN GP15.phx.gbl...
      I have a user control that contains three variables which are accessed through public properties. They are declared immediately below the "Web Form Designer Generated Code" section. Every time an event is fired by one of the controls contained in the User Control, these variable are reset. Here is my current code (I have a little more to add later, right now I am just concerned about the variables getting reset):


      Public Class DatePicker2
      Inherits System.Web.UI.U serControl

      #Region " Web Form Designer Generated Code "
      'This call is required by the Web Form Designer.
      <System.Diagnos tics.DebuggerSt epThrough()> Private Sub InitializeCompo nent()
      End Sub
      Protected WithEvents ddlMonth As System.Web.UI.W ebControls.Drop DownList
      Protected WithEvents ddlDate As System.Web.UI.W ebControls.Drop DownList
      Protected WithEvents ddlYear As System.Web.UI.W ebControls.Drop DownList
      'NOTE: The following placeholder declaration is required by the Web Form Designer.
      'Do not delete or move it.
      Private designerPlaceho lderDeclaration As System.Object
      Private Sub Page_Init(ByVal sender As System.Object, ByVal e As System.EventArg s) Handles MyBase.Init
      'CODEGEN: This method call is required by the Web Form Designer
      'Do not modify it using the code editor.
      InitializeCompo nent()
      End Sub
      #End Region

      Private datevalue As Date = Date.Today
      Private startyear As Integer = 1900
      Private stopyear As Integer = 2100

      Public Property SelectedDate() As Date
      Get
      Return Me.datevalue
      End Get
      Set(ByVal Value As Date)
      Me.datevalue = Value
      Me.CreateLists( )
      End Set
      End Property
      Public Property FirstYear() As Integer
      Get
      Return Me.startyear
      End Get
      Set(ByVal Value As Integer)
      Me.startyear = Value
      End Set
      End Property
      Public Property LastYear() As Integer
      Get
      Return Me.stopyear
      End Get
      Set(ByVal Value As Integer)
      Me.stopyear = Value
      End Set
      End Property

      Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArg s) Handles MyBase.Load
      Me.CreateLists( )
      End Sub

      Private Sub CreateLists()
      'Date is currently set at this point
      ddlMonth.Items. Clear()
      ddlYear.Items.C lear()
      ddlDate.Items.C lear()
      For i As Integer = 1 To 12
      ddlMonth.Items. Add(New ListItem(System .Globalization. DateTimeFormatI nfo.CurrentInfo .GetMonthName(i ), CStr(i)))
      Next
      For j As Integer = Me.startyear To Me.stopyear
      ddlYear.Items.A dd(CStr(j))
      Next
      For i As Integer = 1 To Date.DaysInMont h(Me.datevalue. Year, Me.datevalue.Mo nth)
      ddlDate.Items.A dd(New ListItem(CStr(i ) & " " & System.Globaliz ation.DateTimeF ormatInfo.Curre ntInfo.DayNames (New Date(Me.dateval ue.Year, Me.datevalue.Mo nth, i).DayOfWeek), CStr(i)))
      Next
      ddlMonth.Select edIndex = Me.datevalue.Mo nth - 1
      ddlYear.Selecte dIndex = Me.datevalue.Ye ar - Me.startyear
      ddlDate.Selecte dIndex = Me.datevalue.Da y - 1
      End Sub
      End Class


      <%@ Control Language="vb" AutoEventWireup ="false" Codebehind="Dat ePicker2.ascx.v b" Inherits="WebAp plication1.Date Picker2" TargetSchema="h ttp://schemas.microso ft.com/intellisense/ie5" %>
      <asp:dropdownli st id="ddlMonth" runat="server" AutoPostBack="T rue"></asp:dropdownlis t>
      <asp:dropdownli st id="ddlDate" runat="server" AutoPostBack="T rue"></asp:dropdownlis t>
      <asp:dropdownli st id="ddlYear" runat="server" AutoPostBack="T rue"></asp:dropdownlis t>


      Thank you in advance for your help.
      --
      Nathan Sokalski
      njsokalski@hotm ail.com
      有声小说网-无弹窗小说阅读网
      http://www.nathansokalski.com/
      有声小说网为广大读者提供热门小说在线免费阅读，本站收集的网络文学小说情节跌宕起伏，有声小说网是值得书友们收藏的小说在线阅读网。

        Comment

        • Ken Tucker [MVP]
          #3
          Re: Value of variable in my user control keeps getting reset

          Hi,

          You are loading the values if the pageload event even if you are
          posting back. Try something like this.

          Private Sub Page_Load(ByVal sender As System.Object, ByVal e As
          System.EventArg s) Handles MyBase.Load
          if not ispostback then
          Me.CreateLists( )
          end if
          End Sub

          Ken
          ------------------------
          "Nathan Sokalski" <njsokalski@hot mail.com> wrote in message
          news:uBRGb3WxFH A.4032@TK2MSFTN GP15.phx.gbl...
          I have a user control that contains three variables which are accessed
          through public properties. They are declared immediately below the "Web Form
          Designer Generated Code" section. Every time an event is fired by one of the
          controls contained in the User Control, these variable are reset. Here is my
          current code (I have a little more to add later, right now I am just
          concerned about the variables getting reset):


          Public Class DatePicker2
          Inherits System.Web.UI.U serControl

          #Region " Web Form Designer Generated Code "
          'This call is required by the Web Form Designer.
          <System.Diagnos tics.DebuggerSt epThrough()> Private Sub
          InitializeCompo nent()
          End Sub
          Protected WithEvents ddlMonth As System.Web.UI.W ebControls.Drop DownList
          Protected WithEvents ddlDate As System.Web.UI.W ebControls.Drop DownList
          Protected WithEvents ddlYear As System.Web.UI.W ebControls.Drop DownList
          'NOTE: The following placeholder declaration is required by the Web Form
          Designer.
          'Do not delete or move it.
          Private designerPlaceho lderDeclaration As System.Object
          Private Sub Page_Init(ByVal sender As System.Object, ByVal e As
          System.EventArg s) Handles MyBase.Init
          'CODEGEN: This method call is required by the Web Form Designer
          'Do not modify it using the code editor.
          InitializeCompo nent()
          End Sub
          #End Region

          Private datevalue As Date = Date.Today
          Private startyear As Integer = 1900
          Private stopyear As Integer = 2100

          Public Property SelectedDate() As Date
          Get
          Return Me.datevalue
          End Get
          Set(ByVal Value As Date)
          Me.datevalue = Value
          Me.CreateLists( )
          End Set
          End Property
          Public Property FirstYear() As Integer
          Get
          Return Me.startyear
          End Get
          Set(ByVal Value As Integer)
          Me.startyear = Value
          End Set
          End Property
          Public Property LastYear() As Integer
          Get
          Return Me.stopyear
          End Get
          Set(ByVal Value As Integer)
          Me.stopyear = Value
          End Set
          End Property

          Private Sub Page_Load(ByVal sender As System.Object, ByVal e As
          System.EventArg s) Handles MyBase.Load
          Me.CreateLists( )
          End Sub

          Private Sub CreateLists()
          'Date is currently set at this point
          ddlMonth.Items. Clear()
          ddlYear.Items.C lear()
          ddlDate.Items.C lear()
          For i As Integer = 1 To 12
          ddlMonth.Items. Add(New
          ListItem(System .Globalization. DateTimeFormatI nfo.CurrentInfo .GetMonthName(i ),
          CStr(i)))
          Next
          For j As Integer = Me.startyear To Me.stopyear
          ddlYear.Items.A dd(CStr(j))
          Next
          For i As Integer = 1 To Date.DaysInMont h(Me.datevalue. Year,
          Me.datevalue.Mo nth)
          ddlDate.Items.A dd(New ListItem(CStr(i ) & " " &
          System.Globaliz ation.DateTimeF ormatInfo.Curre ntInfo.DayNames (New
          Date(Me.dateval ue.Year, Me.datevalue.Mo nth, i).DayOfWeek), CStr(i)))
          Next
          ddlMonth.Select edIndex = Me.datevalue.Mo nth - 1
          ddlYear.Selecte dIndex = Me.datevalue.Ye ar - Me.startyear
          ddlDate.Selecte dIndex = Me.datevalue.Da y - 1
          End Sub
          End Class


          <%@ Control Language="vb" AutoEventWireup ="false"
          Codebehind="Dat ePicker2.ascx.v b" Inherits="WebAp plication1.Date Picker2"
          TargetSchema="h ttp://schemas.microso ft.com/intellisense/ie5" %>
          <asp:dropdownli st id="ddlMonth" runat="server"
          AutoPostBack="T rue"></asp:dropdownlis t>
          <asp:dropdownli st id="ddlDate" runat="server"
          AutoPostBack="T rue"></asp:dropdownlis t>
          <asp:dropdownli st id="ddlYear" runat="server"
          AutoPostBack="T rue"></asp:dropdownlis t>


          Thank you in advance for your help.
          --
          Nathan Sokalski
          njsokalski@hotm ail.com
          有声小说网-无弹窗小说阅读网
          http://www.nathansokalski.com/
          有声小说网为广大读者提供热门小说在线免费阅读，本站收集的网络文学小说情节跌宕起伏，有声小说网是值得书友们收藏的小说在线阅读网。



            Comment

            • Nathan Sokalski
              #4
              Re: Value of variable in my user control keeps getting reset

              That idea seems to be working, but I have now run into a problem that is preventing me from using it. For some reason I am unable to retrieve the new value of the SelectedIndex property (it always returns the old one, and the user is therefore unable to change the selected item). Why is this? The latest version of my code is included in a newsgroup message in the microsoft.publi c.dotnet.framew ork.aspnet newsgroup with the subject "When Can I Access the New Value of the SelectedIndex property?" posted at 9/30/2005 8:19 PM. I appreciate any help possible. Thanks.
              --
              Nathan Sokalski
              njsokalski@hotm ail.com
              有声小说网-无弹窗小说阅读网
              http://www.nathansokalski.com/
              有声小说网为广大读者提供热门小说在线免费阅读，本站收集的网络文学小说情节跌宕起伏，有声小说网是值得书友们收藏的小说在线阅读网。


              "S. Justin Gengo" <justin@[no_spam_please]aboutfortunate. com> wrote in message news:OZ9vOwaxFH A.1412@TK2MSFTN GP09.phx.gbl...
              Nathan,

              All page objects are closed/disposed of after the page is sent to the client.

              What this means is that your page is being recreated each time the client connects to it. Your variables are set up in such a way that they are recreated each post back that is why they are reset.

              Whenever you change the variables you're going to need to store their new values somewhere that will persist between the page being sent to the client and then destroyed on the server so you can get the original values back. In this case I would store the values in viewstate and retrieve them on postback.

              For example you could store the width of a control in viewstate like this:

              ' Declare the Width property.
              Public Property Width() As String
              Get
              Return CType(ViewState ("Width"), String)
              End Get
              Set
              ViewState("Widt h") = value
              End Set
              End Property



              --
              Sincerely,

              S. Justin Gengo, MCP
              Web Developer / Programmer

              Attention Required! | Cloudflare
              https://www.aboutfortunate.com


              "Out of chaos comes order."
              Nietzsche
              "Nathan Sokalski" <njsokalski@hot mail.com> wrote in message news:uBRGb3WxFH A.4032@TK2MSFTN GP15.phx.gbl...
              I have a user control that contains three variables which are accessed through public properties. They are declared immediately below the "Web Form Designer Generated Code" section. Every time an event is fired by one of the controls contained in the User Control, these variable are reset. Here is my current code (I have a little more to add later, right now I am just concerned about the variables getting reset):


              Public Class DatePicker2
              Inherits System.Web.UI.U serControl

              #Region " Web Form Designer Generated Code "
              'This call is required by the Web Form Designer.
              <System.Diagnos tics.DebuggerSt epThrough()> Private Sub InitializeCompo nent()
              End Sub
              Protected WithEvents ddlMonth As System.Web.UI.W ebControls.Drop DownList
              Protected WithEvents ddlDate As System.Web.UI.W ebControls.Drop DownList
              Protected WithEvents ddlYear As System.Web.UI.W ebControls.Drop DownList
              'NOTE: The following placeholder declaration is required by the Web Form Designer.
              'Do not delete or move it.
              Private designerPlaceho lderDeclaration As System.Object
              Private Sub Page_Init(ByVal sender As System.Object, ByVal e As System.EventArg s) Handles MyBase.Init
              'CODEGEN: This method call is required by the Web Form Designer
              'Do not modify it using the code editor.
              InitializeCompo nent()
              End Sub
              #End Region

              Private datevalue As Date = Date.Today
              Private startyear As Integer = 1900
              Private stopyear As Integer = 2100

              Public Property SelectedDate() As Date
              Get
              Return Me.datevalue
              End Get
              Set(ByVal Value As Date)
              Me.datevalue = Value
              Me.CreateLists( )
              End Set
              End Property
              Public Property FirstYear() As Integer
              Get
              Return Me.startyear
              End Get
              Set(ByVal Value As Integer)
              Me.startyear = Value
              End Set
              End Property
              Public Property LastYear() As Integer
              Get
              Return Me.stopyear
              End Get
              Set(ByVal Value As Integer)
              Me.stopyear = Value
              End Set
              End Property

              Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArg s) Handles MyBase.Load
              Me.CreateLists( )
              End Sub

              Private Sub CreateLists()
              'Date is currently set at this point
              ddlMonth.Items. Clear()
              ddlYear.Items.C lear()
              ddlDate.Items.C lear()
              For i As Integer = 1 To 12
              ddlMonth.Items. Add(New ListItem(System .Globalization. DateTimeFormatI nfo.CurrentInfo .GetMonthName(i ), CStr(i)))
              Next
              For j As Integer = Me.startyear To Me.stopyear
              ddlYear.Items.A dd(CStr(j))
              Next
              For i As Integer = 1 To Date.DaysInMont h(Me.datevalue. Year, Me.datevalue.Mo nth)
              ddlDate.Items.A dd(New ListItem(CStr(i ) & " " & System.Globaliz ation.DateTimeF ormatInfo.Curre ntInfo.DayNames (New Date(Me.dateval ue.Year, Me.datevalue.Mo nth, i).DayOfWeek), CStr(i)))
              Next
              ddlMonth.Select edIndex = Me.datevalue.Mo nth - 1
              ddlYear.Selecte dIndex = Me.datevalue.Ye ar - Me.startyear
              ddlDate.Selecte dIndex = Me.datevalue.Da y - 1
              End Sub
              End Class


              <%@ Control Language="vb" AutoEventWireup ="false" Codebehind="Dat ePicker2.ascx.v b" Inherits="WebAp plication1.Date Picker2" TargetSchema="h ttp://schemas.microso ft.com/intellisense/ie5" %>
              <asp:dropdownli st id="ddlMonth" runat="server" AutoPostBack="T rue"></asp:dropdownlis t>
              <asp:dropdownli st id="ddlDate" runat="server" AutoPostBack="T rue"></asp:dropdownlis t>
              <asp:dropdownli st id="ddlYear" runat="server" AutoPostBack="T rue"></asp:dropdownlis t>


              Thank you in advance for your help.
              --
              Nathan Sokalski
              njsokalski@hotm ail.com
              有声小说网-无弹窗小说阅读网
              http://www.nathansokalski.com/
              有声小说网为广大读者提供热门小说在线免费阅读，本站收集的网络文学小说情节跌宕起伏，有声小说网是值得书友们收藏的小说在线阅读网。

                Comment

                • S. Justin Gengo
                  #5
                  Re: Value of variable in my user control keeps getting reset

                  Nathan,

                  It sounds as if you may be databinding the control, setting it's SelectedValue, or SelectedIndex on post back. You need to only set databind and/or set the control's selected value on the first page load or the user's choice will be overwritten on each post back. Wrap any of those items in a If Not Page.IsPostBack Then routine and that should take care of it.

                  --
                  Sincerely,

                  S. Justin Gengo, MCP
                  Web Developer / Programmer

                  Attention Required! | Cloudflare
                  https://www.aboutfortunate.com


                  "Out of chaos comes order."
                  Nietzsche
                  "Nathan Sokalski" <njsokalski@hot mail.com> wrote in message news:OhgFUXjxFH A.788@tk2msftng p13.phx.gbl...
                  That idea seems to be working, but I have now run into a problem that is preventing me from using it. For some reason I am unable to retrieve the new value of the SelectedIndex property (it always returns the old one, and the user is therefore unable to change the selected item). Why is this? The latest version of my code is included in a newsgroup message in the microsoft.publi c.dotnet.framew ork.aspnet newsgroup with the subject "When Can I Access the New Value of the SelectedIndex property?" posted at 9/30/2005 8:19 PM. I appreciate any help possible. Thanks.
                  --
                  Nathan Sokalski
                  njsokalski@hotm ail.com
                  有声小说网-无弹窗小说阅读网
                  http://www.nathansokalski.com/
                  有声小说网为广大读者提供热门小说在线免费阅读，本站收集的网络文学小说情节跌宕起伏，有声小说网是值得书友们收藏的小说在线阅读网。


                  "S. Justin Gengo" <justin@[no_spam_please]aboutfortunate. com> wrote in message news:OZ9vOwaxFH A.1412@TK2MSFTN GP09.phx.gbl...
                  Nathan,

                  All page objects are closed/disposed of after the page is sent to the client.

                  What this means is that your page is being recreated each time the client connects to it. Your variables are set up in such a way that they are recreated each post back that is why they are reset.

                  Whenever you change the variables you're going to need to store their new values somewhere that will persist between the page being sent to the client and then destroyed on the server so you can get the original values back. In this case I would store the values in viewstate and retrieve them on postback.

                  For example you could store the width of a control in viewstate like this:

                  ' Declare the Width property.
                  Public Property Width() As String
                  Get
                  Return CType(ViewState ("Width"), String)
                  End Get
                  Set
                  ViewState("Widt h") = value
                  End Set
                  End Property



                  --
                  Sincerely,

                  S. Justin Gengo, MCP
                  Web Developer / Programmer

                  Attention Required! | Cloudflare
                  https://www.aboutfortunate.com


                  "Out of chaos comes order."
                  Nietzsche
                  "Nathan Sokalski" <njsokalski@hot mail.com> wrote in message news:uBRGb3WxFH A.4032@TK2MSFTN GP15.phx.gbl...
                  I have a user control that contains three variables which are accessed through public properties. They are declared immediately below the "Web Form Designer Generated Code" section. Every time an event is fired by one of the controls contained in the User Control, these variable are reset. Here is my current code (I have a little more to add later, right now I am just concerned about the variables getting reset):


                  Public Class DatePicker2
                  Inherits System.Web.UI.U serControl

                  #Region " Web Form Designer Generated Code "
                  'This call is required by the Web Form Designer.
                  <System.Diagnos tics.DebuggerSt epThrough()> Private Sub InitializeCompo nent()
                  End Sub
                  Protected WithEvents ddlMonth As System.Web.UI.W ebControls.Drop DownList
                  Protected WithEvents ddlDate As System.Web.UI.W ebControls.Drop DownList
                  Protected WithEvents ddlYear As System.Web.UI.W ebControls.Drop DownList
                  'NOTE: The following placeholder declaration is required by the Web Form Designer.
                  'Do not delete or move it.
                  Private designerPlaceho lderDeclaration As System.Object
                  Private Sub Page_Init(ByVal sender As System.Object, ByVal e As System.EventArg s) Handles MyBase.Init
                  'CODEGEN: This method call is required by the Web Form Designer
                  'Do not modify it using the code editor.
                  InitializeCompo nent()
                  End Sub
                  #End Region

                  Private datevalue As Date = Date.Today
                  Private startyear As Integer = 1900
                  Private stopyear As Integer = 2100

                  Public Property SelectedDate() As Date
                  Get
                  Return Me.datevalue
                  End Get
                  Set(ByVal Value As Date)
                  Me.datevalue = Value
                  Me.CreateLists( )
                  End Set
                  End Property
                  Public Property FirstYear() As Integer
                  Get
                  Return Me.startyear
                  End Get
                  Set(ByVal Value As Integer)
                  Me.startyear = Value
                  End Set
                  End Property
                  Public Property LastYear() As Integer
                  Get
                  Return Me.stopyear
                  End Get
                  Set(ByVal Value As Integer)
                  Me.stopyear = Value
                  End Set
                  End Property

                  Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArg s) Handles MyBase.Load
                  Me.CreateLists( )
                  End Sub

                  Private Sub CreateLists()
                  'Date is currently set at this point
                  ddlMonth.Items. Clear()
                  ddlYear.Items.C lear()
                  ddlDate.Items.C lear()
                  For i As Integer = 1 To 12
                  ddlMonth.Items. Add(New ListItem(System .Globalization. DateTimeFormatI nfo.CurrentInfo .GetMonthName(i ), CStr(i)))
                  Next
                  For j As Integer = Me.startyear To Me.stopyear
                  ddlYear.Items.A dd(CStr(j))
                  Next
                  For i As Integer = 1 To Date.DaysInMont h(Me.datevalue. Year, Me.datevalue.Mo nth)
                  ddlDate.Items.A dd(New ListItem(CStr(i ) & " " & System.Globaliz ation.DateTimeF ormatInfo.Curre ntInfo.DayNames (New Date(Me.dateval ue.Year, Me.datevalue.Mo nth, i).DayOfWeek), CStr(i)))
                  Next
                  ddlMonth.Select edIndex = Me.datevalue.Mo nth - 1
                  ddlYear.Selecte dIndex = Me.datevalue.Ye ar - Me.startyear
                  ddlDate.Selecte dIndex = Me.datevalue.Da y - 1
                  End Sub
                  End Class


                  <%@ Control Language="vb" AutoEventWireup ="false" Codebehind="Dat ePicker2.ascx.v b" Inherits="WebAp plication1.Date Picker2" TargetSchema="h ttp://schemas.microso ft.com/intellisense/ie5" %>
                  <asp:dropdownli st id="ddlMonth" runat="server" AutoPostBack="T rue"></asp:dropdownlis t>
                  <asp:dropdownli st id="ddlDate" runat="server" AutoPostBack="T rue"></asp:dropdownlis t>
                  <asp:dropdownli st id="ddlYear" runat="server" AutoPostBack="T rue"></asp:dropdownlis t>


                  Thank you in advance for your help.
                  --
                  Nathan Sokalski
                  njsokalski@hotm ail.com
                  有声小说网-无弹窗小说阅读网
                  http://www.nathansokalski.com/
                  有声小说网为广大读者提供热门小说在线免费阅读，本站收集的网络文学小说情节跌宕起伏，有声小说网是值得书友们收藏的小说在线阅读网。

                    Comment

                    • Nathan Sokalski
                      #6
                      Re: Value of variable in my user control keeps getting reset

                      Here is my latest version of the User Control. This version uses 3 viewstate keys instead of actual variables. My problem is that when I attempt to access any of the SelectedIndex properties they report an incorrect value. When I did a debug they reported an incorrect value even when the only place I assign a value to SelectedIndex is never executed (and it never gets executed until after I use the SelectedIndex anyway). Somebody please tell me why I can't access the new SelectedIndex value? Thanks, here is my most recent code:


                      Public Class DatePicker
                      Inherits System.Web.UI.U serControl

                      #Region " Web Form Designer Generated Code "

                      'This call is required by the Web Form Designer.
                      <System.Diagnos tics.DebuggerSt epThrough()> Private Sub InitializeCompo nent()
                      End Sub
                      Protected WithEvents ddlMonth As System.Web.UI.W ebControls.Drop DownList
                      Protected WithEvents ddlDate As System.Web.UI.W ebControls.Drop DownList
                      Protected WithEvents ddlYear As System.Web.UI.W ebControls.Drop DownList

                      'NOTE: The following placeholder declaration is required by the Web Form Designer.
                      'Do not delete or move it.
                      Private designerPlaceho lderDeclaration As System.Object

                      Private Sub Page_Init(ByVal sender As System.Object, ByVal e As System.EventArg s) Handles MyBase.Init
                      'CODEGEN: This method call is required by the Web Form Designer
                      'Do not modify it using the code editor.
                      InitializeCompo nent()
                      End Sub
                      #End Region

                      Public Property SelectedDate() As Date
                      Get
                      Return CDate(ViewState ("datevalue" ))
                      End Get
                      Set(ByVal Value As Date)
                      ViewState("date value") = Value
                      ViewState("star tyear") = Math.Min(CDate( ViewState("date value")).Year, CInt(ViewState( "startyear" )))
                      ViewState("stop year") = Math.Max(CDate( ViewState("date value")).Year, CInt(ViewState( "stopyear") ))
                      Me.CreateLists( )
                      End Set
                      End Property
                      Public Property FirstYear() As Integer
                      Get
                      Return CInt(ViewState( "startyear" ))
                      End Get
                      Set(ByVal Value As Integer)
                      If Value <= CDate(ViewState ("datevalue")). Year AndAlso Value >= 1 Then
                      ViewState("star tyear") = Value
                      Me.CreateLists( )
                      End If
                      End Set
                      End Property
                      Public Property LastYear() As Integer
                      Get
                      Return CInt(ViewState( "stopyear") )
                      End Get
                      Set(ByVal Value As Integer)
                      If Value >= CDate(ViewState ("datevalue")). Year AndAlso Value <= 9999 Then
                      ViewState("stop year") = Value
                      Me.CreateLists( )
                      End If
                      End Set
                      End Property

                      Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArg s) Handles MyBase.Load
                      If Not IsPostBack() Then
                      ViewState.Add(" datevalue", Date.Today)
                      ViewState.Add(" startyear", 1950)
                      ViewState.Add(" stopyear", 2050)
                      For i As Integer = 1 To 12
                      ddlMonth.Items. Add(New ListItem(System .Globalization. DateTimeFormatI nfo.CurrentInfo .GetMonthName(i ), CStr(i)))
                      Next
                      Me.CreateLists( )
                      End If
                      End Sub

                      Private Sub CreateLists()
                      ddlYear.Items.C lear()
                      ddlDate.Items.C lear()
                      For j As Integer = CInt(ViewState( "startyear" )) To CInt(ViewState( "stopyear") )
                      ddlYear.Items.A dd(CStr(j))
                      Next
                      For i As Integer = 1 To Date.DaysInMont h(CDate(ViewSta te("datevalue") ).Year, CDate(ViewState ("datevalue")). Month)
                      ddlDate.Items.A dd(New ListItem(CStr(i ) & " " & System.Globaliz ation.DateTimeF ormatInfo.Curre ntInfo.DayNames (New Date(CDate(View State("datevalu e")).Year, CDate(ViewState ("datevalue")). Month, i).DayOfWeek), CStr(i)))
                      Next
                      ddlMonth.Select edIndex = CDate(ViewState ("datevalue")). Month - 1
                      ddlYear.Selecte dIndex = CDate(ViewState ("datevalue")). Year - CInt(ViewState( "startyear" ))
                      ddlDate.Selecte dIndex = CDate(ViewState ("datevalue")). Day - 1
                      End Sub

                      Private Sub DateChanged(ByV al sender As Object, ByVal e As System.EventArg s) Handles ddlMonth.Select edIndexChanged, ddlYear.Selecte dIndexChanged, ddlDate.Selecte dIndexChanged
                      Dim selectedyear As Integer = ddlYear.Selecte dIndex + CInt(ViewState( "startyear" ))
                      Dim selectedmonth As Integer = ddlMonth.Select edIndex + 1
                      Dim selectedday As Integer = ddlDate.Selecte dIndex + 1
                      ViewState("date value") = New Date(selectedye ar, selectedmonth, Math.Min(Date.D aysInMonth(sele ctedyear, selectedmonth), selectedday))
                      Me.CreateLists( )
                      End Sub
                      End Class




                      <%@ Control Language="vb" AutoEventWireup ="false" Codebehind="Dat ePicker.ascx.vb " Inherits="WebAp plication1.Date Picker" TargetSchema="h ttp://schemas.microso ft.com/intellisense/ie5" %>
                      <asp:dropdownli st id="ddlMonth" AutoPostBack="T rue" runat="server"> </asp:dropdownlis t>
                      <asp:dropdownli st id="ddlDate" AutoPostBack="T rue" runat="server"> </asp:dropdownlis t>
                      <asp:dropdownli st id="ddlYear" AutoPostBack="T rue" runat="server"> </asp:dropdownlis t>
                      --
                      Nathan Sokalski
                      njsokalski@hotm ail.com
                      有声小说网-无弹窗小说阅读网
                      http://www.nathansokalski.com/
                      有声小说网为广大读者提供热门小说在线免费阅读，本站收集的网络文学小说情节跌宕起伏，有声小说网是值得书友们收藏的小说在线阅读网。

                      "S. Justin Gengo" <justin@[no_spam_please]aboutfortunate. com> wrote in message news:ew1krNCyFH A.908@tk2msftng p13.phx.gbl...
                      Nathan,

                      It sounds as if you may be databinding the control, setting it's SelectedValue, or SelectedIndex on post back. You need to only set databind and/or set the control's selected value on the first page load or the user's choice will be overwritten on each post back. Wrap any of those items in a If Not Page.IsPostBack Then routine and that should take care of it.

                      --
                      Sincerely,

                      S. Justin Gengo, MCP
                      Web Developer / Programmer

                      Attention Required! | Cloudflare
                      https://www.aboutfortunate.com


                      "Out of chaos comes order."
                      Nietzsche
                      "Nathan Sokalski" <njsokalski@hot mail.com> wrote in message news:OhgFUXjxFH A.788@tk2msftng p13.phx.gbl...
                      That idea seems to be working, but I have now run into a problem that is preventing me from using it. For some reason I am unable to retrieve the new value of the SelectedIndex property (it always returns the old one, and the user is therefore unable to change the selected item). Why is this? The latest version of my code is included in a newsgroup message in the microsoft.publi c.dotnet.framew ork.aspnet newsgroup with the subject "When Can I Access the New Value of the SelectedIndex property?" posted at 9/30/2005 8:19 PM. I appreciate any help possible. Thanks.
                      --
                      Nathan Sokalski
                      njsokalski@hotm ail.com
                      有声小说网-无弹窗小说阅读网
                      http://www.nathansokalski.com/
                      有声小说网为广大读者提供热门小说在线免费阅读，本站收集的网络文学小说情节跌宕起伏，有声小说网是值得书友们收藏的小说在线阅读网。


                      "S. Justin Gengo" <justin@[no_spam_please]aboutfortunate. com> wrote in message news:OZ9vOwaxFH A.1412@TK2MSFTN GP09.phx.gbl...
                      Nathan,

                      All page objects are closed/disposed of after the page is sent to the client.

                      What this means is that your page is being recreated each time the client connects to it. Your variables are set up in such a way that they are recreated each post back that is why they are reset.

                      Whenever you change the variables you're going to need to store their new values somewhere that will persist between the page being sent to the client and then destroyed on the server so you can get the original values back. In this case I would store the values in viewstate and retrieve them on postback.

                      For example you could store the width of a control in viewstate like this:

                      ' Declare the Width property.
                      Public Property Width() As String
                      Get
                      Return CType(ViewState ("Width"), String)
                      End Get
                      Set
                      ViewState("Widt h") = value
                      End Set
                      End Property



                      --
                      Sincerely,

                      S. Justin Gengo, MCP
                      Web Developer / Programmer

                      Attention Required! | Cloudflare
                      https://www.aboutfortunate.com


                      "Out of chaos comes order."
                      Nietzsche
                      "Nathan Sokalski" <njsokalski@hot mail.com> wrote in message news:uBRGb3WxFH A.4032@TK2MSFTN GP15.phx.gbl...
                      I have a user control that contains three variables which are accessed through public properties. They are declared immediately below the "Web Form Designer Generated Code" section. Every time an event is fired by one of the controls contained in the User Control, these variable are reset. Here is my current code (I have a little more to add later, right now I am just concerned about the variables getting reset):


                      Public Class DatePicker2
                      Inherits System.Web.UI.U serControl

                      #Region " Web Form Designer Generated Code "
                      'This call is required by the Web Form Designer.
                      <System.Diagnos tics.DebuggerSt epThrough()> Private Sub InitializeCompo nent()
                      End Sub
                      Protected WithEvents ddlMonth As System.Web.UI.W ebControls.Drop DownList
                      Protected WithEvents ddlDate As System.Web.UI.W ebControls.Drop DownList
                      Protected WithEvents ddlYear As System.Web.UI.W ebControls.Drop DownList
                      'NOTE: The following placeholder declaration is required by the Web Form Designer.
                      'Do not delete or move it.
                      Private designerPlaceho lderDeclaration As System.Object
                      Private Sub Page_Init(ByVal sender As System.Object, ByVal e As System.EventArg s) Handles MyBase.Init
                      'CODEGEN: This method call is required by the Web Form Designer
                      'Do not modify it using the code editor.
                      InitializeCompo nent()
                      End Sub
                      #End Region

                      Private datevalue As Date = Date.Today
                      Private startyear As Integer = 1900
                      Private stopyear As Integer = 2100

                      Public Property SelectedDate() As Date
                      Get
                      Return Me.datevalue
                      End Get
                      Set(ByVal Value As Date)
                      Me.datevalue = Value
                      Me.CreateLists( )
                      End Set
                      End Property
                      Public Property FirstYear() As Integer
                      Get
                      Return Me.startyear
                      End Get
                      Set(ByVal Value As Integer)
                      Me.startyear = Value
                      End Set
                      End Property
                      Public Property LastYear() As Integer
                      Get
                      Return Me.stopyear
                      End Get
                      Set(ByVal Value As Integer)
                      Me.stopyear = Value
                      End Set
                      End Property

                      Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArg s) Handles MyBase.Load
                      Me.CreateLists( )
                      End Sub

                      Private Sub CreateLists()
                      'Date is currently set at this point
                      ddlMonth.Items. Clear()
                      ddlYear.Items.C lear()
                      ddlDate.Items.C lear()
                      For i As Integer = 1 To 12
                      ddlMonth.Items. Add(New ListItem(System .Globalization. DateTimeFormatI nfo.CurrentInfo .GetMonthName(i ), CStr(i)))
                      Next
                      For j As Integer = Me.startyear To Me.stopyear
                      ddlYear.Items.A dd(CStr(j))
                      Next
                      For i As Integer = 1 To Date.DaysInMont h(Me.datevalue. Year, Me.datevalue.Mo nth)
                      ddlDate.Items.A dd(New ListItem(CStr(i ) & " " & System.Globaliz ation.DateTimeF ormatInfo.Curre ntInfo.DayNames (New Date(Me.dateval ue.Year, Me.datevalue.Mo nth, i).DayOfWeek), CStr(i)))
                      Next
                      ddlMonth.Select edIndex = Me.datevalue.Mo nth - 1
                      ddlYear.Selecte dIndex = Me.datevalue.Ye ar - Me.startyear
                      ddlDate.Selecte dIndex = Me.datevalue.Da y - 1
                      End Sub
                      End Class


                      <%@ Control Language="vb" AutoEventWireup ="false" Codebehind="Dat ePicker2.ascx.v b" Inherits="WebAp plication1.Date Picker2" TargetSchema="h ttp://schemas.microso ft.com/intellisense/ie5" %>
                      <asp:dropdownli st id="ddlMonth" runat="server" AutoPostBack="T rue"></asp:dropdownlis t>
                      <asp:dropdownli st id="ddlDate" runat="server" AutoPostBack="T rue"></asp:dropdownlis t>
                      <asp:dropdownli st id="ddlYear" runat="server" AutoPostBack="T rue"></asp:dropdownlis t>


                      Thank you in advance for your help.
                      --
                      Nathan Sokalski
                      njsokalski@hotm ail.com
                      有声小说网-无弹窗小说阅读网
                      http://www.nathansokalski.com/
                      有声小说网为广大读者提供热门小说在线免费阅读，本站收集的网络文学小说情节跌宕起伏，有声小说网是值得书友们收藏的小说在线阅读网。

                        Comment

                        Previous template Next
                        Working...