asked on

Add javascript event handler to a web control - in 1.1.

I'm attempting to implement a set of javascript functions that produce type ahead functionality for a .net dropdown list box as found at:
http://aspalliance.com/articleViewer.aspx?aId=775&pId=-1

Alas, that solution assumes .net 2.0 where the code-behind rests on using the block below. I _think this is doing nothing more complicated than assigning a javascript function to an event on the rendered web control...can that be achieved in the 1.1 framework?

{
Type typ = GetType();
if (!Page.ClientScript.IsClientScriptIncludeRegistered(typ, js))
Page.ClientScript.RegisterClientScriptInclude(typ, js, js);
ddlTest.Attributes.Add("onKeyDown", "TADD_OnKeyDown(this);");
}

thx
--steve...

ASKER CERTIFIED SOLUTION

Roopesh_7

membership

This solution is only available to members.

To access this solution, you must be a member of Experts Exchange.

Start Free Trial

juststeve

ASKER

Thankx...I've been able to get basic functionality working by using:

Dim scriptString As String
scriptString = "<script language=JavaScript>"
scriptString = scriptString & "TADD_OnKeyDown(this);"
scriptString = scriptString & "</script>"

If (Not IsStartupScriptRegistered("ddFindUser")) Then
RegisterStartupScript("ddFindUser", scriptString.ToString)
End If

ddFindUser.Attributes.Add("onKeyDown", "TADD_OnKeyDown(this);")

Where I'm populating a dropdown thusly:
ddFindUser.DataSource = ds.Tables(0).DefaultView
ddFindUser.DataTextField = "strUName"
ddFindUser.DataValueField = "UserIdentity"
ddFindUser.Items.Insert(0, "All")
ddFindUser.DataBind()

That produces this line in the rendered control:
<select name="ddFindUser" id="ddFindUser" onKeyDown="TADD_OnKeyDown(this);">
(Since I don't have any 2.0 projects setup i can't run a test against the original code to see how _it renders the HTML control, but this certainly _looks like it should look....

And the type ahead functionality _does, in fact, work. However...after IE has loaded the page it reports a javascript error occurred at this point in one of the js functions that, to all outward appearances, is working correctly:

function TADD_OnKeyDown(tb)
{
if (event.ctrlKey) //this line reports error: 'Object required'
return;

NOTE: the error is reported via the status bar page load indicator...not a popup dialog explicitly presented to the user.

juststeve

ASKER

it appears that the only thing I need to do is:
ddFindUser.Attributes.Add("onKeyDown", "TADD_OnKeyDown(this);")

The RegisterStartupScript block is not needed. It appears that block had been adding an addtional line at the page level causeing the error.