Accessing DIV style properties from Code Behind page.

[albertlse]

I am currently working on an ASCX page.

On the ASCX page, I have a DIV that looks like this:

<div id="divElement0"></div>

On the ASCX code behind page, I set the DIV style properties on Page_Load():

    Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load

        Dim strScript As New StringBuilder

        If Not Page.IsPostBack Then

            strScript.Append("document.getElementById('divElement0').innerText = ""xxx"";")
            strScript.Append("document.getElementById('divElement0').style.left = ""354px"";")
            strScript.Append("document.getElementById('divElement0').style.top = ""194px"";")

        End If

        Page.ClientScript.RegisterStartupScript(Me.GetType(), "test", strScript.ToString, True)

    End Sub

The page loaded successfully, with the DIV appeared as set. I can also change the position of the DIV by dragging it around.

Now, I am having problem when I try to retrieve the DIV style properties value via a button click.

    Protected Sub Button1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button1.Click
        Page.ClientScript.RegisterStartupScript(Me.GetType(), "test2", "alert(document.getElementById('divElement0').style.left);", True)
    End Sub

I expect it will show the DIV's left position as 354px or whatever it is depending on where I dragged it to. However it just show nothing in the message box.

How can I fixed this? Please help. Thank you.

[jigabyte]

Try using ASP:Panel rather than a DIV; you can then access it in the Code Behind.

[crabback]

You need to set the runat="server" attribute of the control in order to access it from the code behind so:
<div id="divElement0"></div>
becomes
<div id="divElement0" runat="server"></div>