passing variable from VB function to client side javascript

Question

hello i am using this Page.ClientScript.RegisterStartupScript() to call a javascript function from vb code behind , and this works fine with me My question is how can i send variables from the code behind to the javascript function here is what i have tried so far :

 Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs)
 Handles Me.LoadComplete
 Dim Myname As String = "myName"
 Dim cstype As Type = Me.GetType()
 Page.ClientScript.RegisterStartupScript(cstype, "MyKey", "hello(Myname);",
 True)
End Sub 

javascript :

 <script type="text/javascript">
 function hello(name) {
 alert("hello world from javascript " + name)
 }
</script>

Thank you ...

Answer 1

You have to use correct quotations to pass strings:

Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs)
 Handles Me.LoadComplete
 Dim Myname As String = "myName"
 Dim cstype As Type = Me.GetType()
 Page.ClientScript.RegisterStartupScript(cstype, "MyKey", "hello('" & Myname & "');",
 True)
End Sub 

Note single quotes around variable name.

Another way for bi-directional passing of data between client and server-side code is hidden fields, e.g

<asp:HiddenField ID="xhidMyname" runat="server" />

or

<input type="hidden" id="xhidMyname" runat="server" />

This field will be accessible both client-side and server side via it's "value" property.

Answer 2

Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs)
 Handles Me.LoadComplete
 Dim Myname As String = "myName"
 Dim cstype As Type = Me.GetType()
 Page.ClientScript.RegisterStartupScript(cstype, "MyKey", "hello('"&Myname&"');",
 True)
End Sub 

• Rab Khan: ya, sorry I missed to add single quote around the string