Paging by example - help - still no luck....

[Tmuld]

Hello,

I was looking at the example provided on:

http://www.4guysfromrolla.com/webtech/072101-1.2.shtml

for paging.

I am using Visual Studio 2003 - Microsoft Development Environment 2003

For paging the page url mentions setting properties to be set as:

AllowPaging="Tr ue"
PageSize="15"
OnPageIndexChan ged="dgPopularF AQs_Paged">

Ok. I am looking at my datagrid in the design view - there is a Allow
Paging, PageSize - but no OnPageIndexChan ged!!

I went to the code behine - at the top selected my datagrid in the top
left drop down menu, and could not find OnPageIndexChan ged in the
declarations menu. There is a 'PageIndexChang ed' changed - is that it?

Well, I put this code in that area (using a Dataset called ds):


Private Sub dg_PageIndexCha nged(ByVal source As Object, ByVal e As
System.Web.UI.W ebControls.Data GridPageChanged EventArgs) Handles
dg.PageIndexCha nged
dg.CurrentPageI ndex = e.NewPageIndex
dg.DataBind()
End Sub

The paging numbers show up on the grid, but when I hit any of the
numbers - the same screen shows up - 10 records, it does not advance
(set to 10 in the property builder). It never advances. In my page
load I have this:

Private Sub Page_Load(ByVal sender As System.Object, ByVal e As
System.EventArg s) Handles MyBase.Load
'Put user code to initialize the page here
If Not Page.IsPostBack Then

dgDataBind()
End If
End Sub

Any help?

Thanks,

Tmuld

[Cor Ligthert]

Re: Paging by example - help - still no luck....

Tmuld,

Why don't you just use the samples on MSDN for paging a datagrid, they are
in my opinion very well.

One of them

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dv_vbcode/html/vbtskCodePagingInDataGridWebControlVisualBasic.asp

I hope this helps,

Cor

[Tmuld]

Re: Paging by example - help - still no luck....

Thanks - it does work very well!

I still have some issues. I used the MSDN code and it sort of works.
Now the paging works, but when I hit the number - it does not show my
records until I hit the search button again. I thought it would go to
the next records automatically. Not sure why? Do I need to do some
sort of refresh at the button level?

[Plus I also do not understand this line:

dsQuery = CType(Session(" dataset"), DataSet1). I already have a
dataset defined at design time - what does this do? ]

Here is my code:
- my dataset is called 'ds'

Private Sub Page_Load(ByVal sender As System.Object, ByVal e As
System.EventArg s) Handles MyBase.Load
'Put user code to initialize the page here
With dg
.AllowPaging = True
.PagerStyle.Mod e = PagerMode.Numer icPages
.PageSize = 5
.PagerStyle.Pag eButtonCount = 5
End With
If IsPostBack Then
ds = CType(Session(" dataset"), DataSet1)
Else
daQuery.Fill(ds )
Session("datase t") = ds
DataBind()
End If
End Sub

The button code->filters out data with a dataview. So after the page
button is pressed - one gets a blank screen untill the button is
pressed again - then it moves to the next results.

Private Sub btn_Click(ByVal sender As System.Object, ByVal e As
System.EventArg s) Handles btn.Click
Dim Count As Integer

Dim dv As DataView = ds.Tables("DB") .DefaultView
dv.RowFilter = "Title like '%" & txt.Text & "%' OR Address like
'%" & txt.Text & "%'"
Count = dv.Count
dg.DataSource = dv
dg.DataBind()
lblCount.Text = Count

End Sub

Paging:

Private Sub dg_PageIndexCha nged(ByVal source As Object, ByVal e As
System.Web.UI.W ebControls.Data GridPageChanged EventArgs) Handles
dg.PageIndexCha nged
dg.CurrentPageI ndex = e.NewPageIndex
dg.DataBind()
End Sub

[Cor Ligthert]

Re: Paging by example - help - still no luck....

Tmuld,

A webpage is not persistent, what means that with every send and get back
all the data on serverside is removed. For that are some solutions for with
is the session the most simple. The most simple because it can fit
automatically (serialized) the dataset.

Therefore you have to set that dataset again when there is a postback to the
session (and as well when you do a fill to renew it).

Your other question is what I am always struggling with as well, so take
some time to find that.

Cor

[Tmuldoon]

Re: Paging by example - help - still no luck....

It is strange it is actually working in the background, but only
appears after the search button is pressed again.

I am thinking the currentrowindex is updated, but only will show when
requeried.

I thought the Databind() property refreshed to the new index.

Still no luck....

[Cor Ligthert]

Re: Paging by example - help - still no luck....

Tmuld,

I made a complete working sample from that what I showed on MSDN in the
link.

Maybe you can try it.
\\\Needs only a webdagrid.
Private Sub Page_Load(ByVal sender As System.Object, _
ByVal e As System.EventArg s) Handles MyBase.Load
Dim ds As DataSet
DataGrid1.Allow Paging = True
DataGrid1.Pager Style.Mode = PagerMode.Numer icPages
DataGrid1.PageS ize = 5
DataGrid1.Pager Style.PageButto nCount = 5
If IsPostBack Then
ds = DirectCast(Sess ion("dataset"), DataSet)
DataGrid1.DataS ource = ds
Else
ds = New DataSet
Dim dt As New DataTable
dt.Columns.Add( "Mycolumn")
For i As Integer = 0 To 100
dt.LoadDataRow( New Object() {i.ToString}, True)
Next
ds.Tables.Add(d t)
Session("datase t") = ds
DataGrid1.DataS ource = ds
DataBind()
End If
End Sub

Private Sub DataGrid1_PageI ndexChanged(ByV al source As Object, ByVal e _
As System.Web.UI.W ebControls.Data GridPageChanged EventArgs) _
Handles DataGrid1.PageI ndexChanged
DataGrid1.Curre ntPageIndex = e.NewPageIndex
DataGrid1.DataB ind()
End Sub
///

I hope this helps a little bit?

Cor

[Tmuld]

Re: Paging by example - help - still no luck....

Hey Cor! I appreciate that!

I tried that example - it is what I am using. I had to fiddle with the
placement of the databinds.

Of course now I have to get paging working and my select buttons on the
side are ignored!

Fix one thing - it leads to another issue!

Thanks for your time and help!

Tmuld

[Tmuld]

Re: Paging by example - help - still no luck....

I mean sorting! Sorting is another strange animal.

And trying to make my BACK button work so it doesn't clear the grid
data and query. And of course asking the user to hit the 'back' button
on the browser is a "no go").

Tmuld