The ASP label id is Label1 and the ClientID in javascript is just need to be there. You cannot do
document.getElementById(“Label1”).innerHTML = SelValue;
it just won’t work.
What you need is
document.getElementById(‘<%= Label1.ClientID %>‘).innerHTML = SelValue;
The complete code is like below.
<%@PageLanguage=”C#”AutoEventWireup=”true”CodeBehind=”WebForm1.aspx.cs”Inherits=”WebAppJSDropDown.WebForm1″%>
<!DOCTYPEhtmlPUBLIC“-//W3C//DTD XHTML 1.0 Transitional//EN”“http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd”>
<htmlxmlns=”http://www.w3.org/1999/xhtml”>
<headrunat=”server”>
<title></title>
</head>
<body>
<scriptlanguage=”javascript”>
function OnChange(dropdown) {
var myindex = dropdown.selectedIndex;
var SelValue = dropdown.options[myindex].value;
document.getElementById(‘<%= Label1.ClientID %>‘).innerHTML = SelValue;
returntrue;
}
</script>
<formid=”form1″runat=”server”>
<div>
<asp:LabelID=”Label1″runat=”server”Text=”Label”></asp:Label>
<selectname=”select1″onchange=’OnChange(this.form.select1);’>
<option>Value 1</option>
<option>Value 2</option>
<option>Value 3</option>
</select>
</div>
</form>
</body>
</html>
You can also download a single solution from http://skydrive.live.com. The sample file name is WebAppJSDropDown.rar My MSN ID is chanmmn@hotmail.com.
Resources:
http://stackoverflow.com/questions/4946013/set-asp-literal-text-with-javascript
