javascript troubleshooting

[MattB]

I'm just trying to do some simple javascript in a form to convert Lbs in
one textbox to kg in another. I'm doing the following inside a If Not
IsPostBack block:

Dim strLbs2kg As String
strLbs2kg = "<script language='javas cript'> " & _
"function Lbs2kg() " & _
"{" & _
"var Lbs = 0; " & _
"Lbs = " & txtWeight.Clien tID & ".value; " & _
txtWeight_m.Cli entID & ".value = Lbs*0.454; " & _
"}" & _
"</script>"
Page.RegisterCl ientScriptBlock ("Lbs2kg", strLbs2kg)
txtWeight.Attri butes.Add("onCh ange", "Lbs2kg()")

But when I type into my txtWeight box and tab off, the kg field is not
populated and I get an script error in the browser saying:

Error: 'txtWeight' is undefined
Code: 0

I thought the ClientID were automatically generated. Id that not true?
Any hints on making this work? Thanks!

Matt

[Chris Botha]

Re: javascript troubleshooting

The ClientID is only valid in the code-behind, so you must declare a
variable up top in your class that can be accessed from the Java script,
like
Protected m_TextWeightCln tId as String
then in your page load, do
m_TextWeightCln tId = TextWeight.Clie ntID
then to get hold of it in the Java script
var theTxtBox = document.GetEle mentById("<%=m_ TextWeightClntI d%>");

"MattB" <somedudeus@yah oo.com> wrote in message
news:3ujnavF11c a53U1@individua l.net...[color=blue]
> I'm just trying to do some simple javascript in a form to convert Lbs in
> one textbox to kg in another. I'm doing the following inside a If Not
> IsPostBack block:
>
> Dim strLbs2kg As String
> strLbs2kg = "<script language='javas cript'> " & _
> "function Lbs2kg() " & _
> "{" & _
> "var Lbs = 0; " & _
> "Lbs = " & txtWeight.Clien tID & ".value; " & _
> txtWeight_m.Cli entID & ".value = Lbs*0.454; " & _
> "}" & _
> "</script>"
> Page.RegisterCl ientScriptBlock ("Lbs2kg", strLbs2kg)
> txtWeight.Attri butes.Add("onCh ange", "Lbs2kg()")
>
> But when I type into my txtWeight box and tab off, the kg field is not
> populated and I get an script error in the browser saying:
>
> Error: 'txtWeight' is undefined
> Code: 0
>
> I thought the ClientID were automatically generated. Id that not true? Any
> hints on making this work? Thanks!
>
> Matt[/color]

[Bruce Barker]

Re: javascript troubleshooting

your code looks correct. is txtWeight visible? if not, it won't render and
the client code will fail. if its not visible switch to a hidden field.

-- bruce (sqlwork.com)


"MattB" <somedudeus@yah oo.com> wrote in message
news:3ujnavF11c a53U1@individua l.net...[color=blue]
> I'm just trying to do some simple javascript in a form to convert Lbs in
> one textbox to kg in another. I'm doing the following inside a If Not
> IsPostBack block:
>
> Dim strLbs2kg As String
> strLbs2kg = "<script language='javas cript'> " & _
> "function Lbs2kg() " & _
> "{" & _
> "var Lbs = 0; " & _
> "Lbs = " & txtWeight.Clien tID & ".value; " & _
> txtWeight_m.Cli entID & ".value = Lbs*0.454; " & _
> "}" & _
> "</script>"
> Page.RegisterCl ientScriptBlock ("Lbs2kg", strLbs2kg)
> txtWeight.Attri butes.Add("onCh ange", "Lbs2kg()")
>
> But when I type into my txtWeight box and tab off, the kg field is not
> populated and I get an script error in the browser saying:
>
> Error: 'txtWeight' is undefined
> Code: 0
>
> I thought the ClientID were automatically generated. Id that not true? Any
> hints on making this work? Thanks!
>
> Matt[/color]

[Chris Botha]

Re: javascript troubleshooting

Oops, sorry, you are building the Java script in the code-behind, so it will
have the right ID, ignore my message above.
The Java script will not find the boxes though, do it like
"Lbs = Form1." & txtWeight.Clien tID & ".value; ......
thus put a "Form1." in front.

"MattB" <somedudeus@yah oo.com> wrote in message
news:3ujnavF11c a53U1@individua l.net...[color=blue]
> I'm just trying to do some simple javascript in a form to convert Lbs in
> one textbox to kg in another. I'm doing the following inside a If Not
> IsPostBack block:
>
> Dim strLbs2kg As String
> strLbs2kg = "<script language='javas cript'> " & _
> "function Lbs2kg() " & _
> "{" & _
> "var Lbs = 0; " & _
> "Lbs = " & txtWeight.Clien tID & ".value; " & _
> txtWeight_m.Cli entID & ".value = Lbs*0.454; " & _
> "}" & _
> "</script>"
> Page.RegisterCl ientScriptBlock ("Lbs2kg", strLbs2kg)
> txtWeight.Attri butes.Add("onCh ange", "Lbs2kg()")
>
> But when I type into my txtWeight box and tab off, the kg field is not
> populated and I get an script error in the browser saying:
>
> Error: 'txtWeight' is undefined
> Code: 0
>
> I thought the ClientID were automatically generated. Id that not true? Any
> hints on making this work? Thanks!
>
> Matt[/color]

[MattB]

Re: javascript troubleshooting

Thanks for the replies. I ended up with a variation of this idea. It works.

Matt

Chris Botha wrote:[color=blue]
> The ClientID is only valid in the code-behind, so you must declare a
> variable up top in your class that can be accessed from the Java script,
> like
> Protected m_TextWeightCln tId as String
> then in your page load, do
> m_TextWeightCln tId = TextWeight.Clie ntID
> then to get hold of it in the Java script
> var theTxtBox = document.GetEle mentById("<%=m_ TextWeightClntI d%>");
>
> "MattB" <somedudeus@yah oo.com> wrote in message
> news:3ujnavF11c a53U1@individua l.net...
>[color=green]
>>I'm just trying to do some simple javascript in a form to convert Lbs in
>>one textbox to kg in another. I'm doing the following inside a If Not
>>IsPostBack block:
>>
>> Dim strLbs2kg As String
>> strLbs2kg = "<script language='javas cript'> " & _
>> "function Lbs2kg() " & _
>> "{" & _
>> "var Lbs = 0; " & _
>> "Lbs = " & txtWeight.Clien tID & ".value; " & _
>> txtWeight_m.Cli entID & ".value = Lbs*0.454; " & _
>> "}" & _
>> "</script>"
>> Page.RegisterCl ientScriptBlock ("Lbs2kg", strLbs2kg)
>> txtWeight.Attri butes.Add("onCh ange", "Lbs2kg()")
>>
>>But when I type into my txtWeight box and tab off, the kg field is not
>>populated and I get an script error in the browser saying:
>>
>>Error: 'txtWeight' is undefined
>>Code: 0
>>
>>I thought the ClientID were automatically generated. Id that not true? Any
>>hints on making this work? Thanks!
>>
>>Matt[/color]
>
>
>[/color]