Execute JavaScript from ASP.NET Server on Page Load

I need to call the following code to render a combox box using JQuery's UI library:

<!-- language: lang-js -->

//renders combobox element with JQueryUI library
function renderComboBox() {
    $("#combobox").combobox();
}

I can execute it just fine when I include the following js in the header:

<!-- language: lang-js -->

//when doc is ready calls into function to render combobox
$(function() {
    renderComboBox();
});

However, based on conditions available at load time, I either need to decide to run or not run the code. I'd like to do that with something similar to the following:

<!-- language: lang-vb -->

Private Sub Page1_Load(sender As Object, e As EventArgs) Handles Me.Load
    If .... Then
        ClientScript.RegisterStartupScript(Me.GetType, _ 
            "RenderCombo", "renderComboBox();", True)
    End If
End Sub

But it doesn't seem to be working. Any thoughts?

Update: Here's a jsFiddle to demonstrate what I'm trying to do, but it's not super helpful because it doesn't help run through any of the ASP.NET specific code.

Because it's all relying on JQuery, you need to make sure your renderComboBox() only fires when the page is ready, So add $(function() { }) code to the code your outputting on your page_load

What is currently happening is your page loads, and the renderComboBox() fires right away - and it will be firing before any of your JQuery or UI is ready.

So try modifying your Javascript to this:

   ClientScript.RegisterStartupScript(Me.GetType, _ 
        "RenderCombo", "$(function() { renderComboBox();})", True)