Then We Use .Length property to check an element is exists and if the element is exists then return total number of match element.

  1. <head id="Head1" runat="server">
  2. <title></title>
  3. <script src="JS/jquery-1.3.2.min.js" type="text/javascript"></script>
  4. <script type="text/javascript">
  5. $(document).ready(function () {
  6. $("#btnGet").click(function () {
  7. if ($('#DivB').length)
  8. { alert("DivA exists"); }
  9. else {
  10. alert("DivB does not exists");
  11. }
  12. });
  13. });
  14. </script>
  15. </head>
  16. <body>
  17. <form id="form1" runat="server">
  18. <div style="padding-left: 100px">
  19. <br />
  20. <div id="DivA">
  21. </div>
  22. <asp:Button ID="btnGet" runat="server" Text="Check If Exists" OnClick="btnGet_Click" />
  23. </div>
  24. </form>
  25. </body>
Output

check if existes

DivB Not Exixts then:

dibB