Call Javascript function from code-behind in C#.NET

Question

Hi

I am trying to call a javascript simple alert function when I catch an exception in my C# code as follows:

inside my function:

try
{
    //something!
}
catch (Exception exc)
{
    ClientScript.RegisterStartupScript(typeof(Page), "SymbolError", 
     "<script type='text/javascript'>alert('Error !!!');return false;</script>");
}

Is there another way I can do this, because this doesn't show any alert boxes or anything??

Answer 1

It's because you'll get the error along the lines of:

Return statement is outside the function

Just do the following, without the return statement:

ClientScript.RegisterStartupScript(typeof(Page), "SymbolError", 
 "<script type='text/javascript'>alert('Error !!!');</script>");

Answer 2

Try this

Page.ClientScript.RegisterClientScriptBlock(this.GetType(), "SymbolError", "alert('error');", true);

Answer 3

The above should work unless if it is inside update panel. For ajax postback, you will have to use ScriptManager.RegisterStartupScript(Page, typeof(Page), "SymbolError", "alert('error!!!')", true); instead.

Answer 4

Its the return, the below code works:

    try
    {
        throw new Exception("lol");
    }
    catch (Exception)
    {
        ClientScript.RegisterStartupScript(typeof(Page), "SymbolError", "<script type='text/javascript'>alert('Error!!!');</script>", false);
    }

Answer 5

Try to use the following:

ScriptManager.RegisterStartupScript(Page, Page.GetType(), "AnUniqueKey", "alert('ERROR');", true);