Below code use error handling in js.
  1. function Navigate() {
  2. try {
  3. addlert("Welcome guest!");
  4. }
  5. catch (err) {
  6. txt = "There was an error on this page.\n\n";
  7. txt += "Error description: " + err.message + "\n\n";
  8. txt += "Click OK to continue.\n\n";
  9. alert(txt);
  10. }
  11. }
  12. </script>
  13. <body>
  14. <form id="form1" runat="server">
  15. <div>
  16. <%-- <asp button type="button" onclick="alert('Welcome!')">Click Me!</button>--%>
  17. <asp:Button ID="Button1" Text="Open Web site" OnClientClick="Navigate()" runat="server" />
  18. </div>
  19. </form>
  20. <body>