call javascript within vb code load function

I’m trying to call Java script code from within the page_load function code, but I don’t know how!!

I’ve added js file to the solution And put in the page

<script type="text/javascript" src="js/hide.js">
// to hide
getElementById("GradesH3").style.display="none";
getElementById("GradesUL").style.display="none";
<开发者_运维知识库;/script>

Now the code where I want to call it is :

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

    If Session("UsrRole") = "Rector" Then

    End If

What you need is:

If Session("UsrRole") = "Rector" Then
   Page.ClientScript.RegisterClientScriptInclude("hide", "js/hide.js")
End If

Remove your existing JS code and change the file "hide.js" to contain this code instead:

window.onload = function() {
   getElementById("GradesH3").style.display = "none";
   getElementById("GradesUL").style.display = "none";
};

Edit: on second thought, more correct way to do that, without using JS at all, it to make GradesH3 and GradesUL be server side by adding runat="server" to them then have such code instead:

If Session("UsrRole") = "Rector" Then
   GradesH3.Visible = False
   GradesUL.Visible = False
End If

You can have any HTML element become server side, for example:

<h3 id="GradesH3" runat="server">I'm header</h3>

There are several way to achieve what you want.

One is to simply output the javascript from your Page_Load - either directly or into a Literal control.

Another is to put the javascript statements into a functions and again, in the page load output a script tag calling the function.

Possibly, the best approach it to use server side controls and control their visibility directly, instead of using javascript.