Change asp based image source: Choosing DropDownList

Question

I want to be able to change the image depending on what is selected in the drop-down list ...

I have JS code to change the image. Simplified, of course.

<script type="text/javascript">
        function changeImage()
        {
            var oDDL = document.all("ddlNAME");
            var NAME= oDDL.options[oDDL.selectedIndex].text;

            switch(NAME)
            {
                case "Name":
                    document.getElementById("img").src="img1.png";
                    break;
                case "Name2":
                    document.getElementById("img").src="img2.png";
                    break;
                default:
                    document.getElementById("img").src="img3.png";
            }
        }
    </script>

When I call this function, I do this in my DDL implementation.

<asp:DropDownList ID="ddlNAME" runat="server" OnTextChanged="changeImage()" >

But for some reason changeImage()does not shoot. it gives me an error saying

'changeImage' is not a member of 'ASP.default_aspx'

I know this is a question about noob, and it's something small ... But this is my first day, each of which uses javascript, so please bring it with me. Thank!

Answer 1

, , , changeImage() ASPX script.

Javascript . onChanged().

<asp:DropDownList ID="ddlNAME" runat="server" onChanged="changeImage();" >

Answer 2

:

<asp:DropDownList ID="ddlNAME" runat="server" onchange="changeImage()" >

, , javascript.

Answer 3

,

<asp:DropDownList ID="ddlNAME" runat="server" onchange="changeImage();" >

OnTextChanged

Answer 4

, , . , , changeImage , , , .

, , document.all. document.getElementById. , document.all DOM 0 , getElementById.

Answer 5

OnTextChanged - ASP.Net, JavaScript. .vb VB, changeImage().

onChange="changeImage()".

this , ( ), getElementById() .

Answer 6

:

<asp:DropDownList ID="ddlNAME" runat="server" onchange="changeImage()" AutoPostBack="false" >

Onchange - javascript, , , ASP.NET. AutoPostBack , ( ), .

Answer 7

JavaScript , "OnChange" DropDownList JS-. "RegisterStartupScript" "RegisterClientScriptBlock".