title: __doPostBack is not a function
body: <pre><code>    &lt;%@ Page Title="" Language="C#" MasterPageFile="~/AdminMaster.Master" AutoEventWireup="true" CodeBehind="MedicalCategory.aspx.cs" Inherits="SanatanJeevan.MedicalCategory" %&gt;
  
          &lt;asp:Content ID="Content1" ContentPlaceHolderID="ContentPlaceHolder3" runat="server"&gt;
              &lt;link href="assets/admin/pages/Prescription.css" rel="stylesheet" /&gt;
  
                 &lt;script&gt;
                  //update button click
                  var btnUpdate = document.getElementById('&lt;%= btnUpdate.ClientID %&gt;');
                  $(function () {
                      $("[id*=btnDelete]").removeAttr("onclick");
                      $('#dialogMedicalCategory').text("Are you sure you want to update?");
                      $('#dialogMedicalCategory').dialog({
                          modal: true,
                          autoOpen: false,
                          title: "Alert",
                          resizable: true,
                          height: "auto",
                          width: 400,
                          buttons: {
                              Ok: function () {
                                  $("[id*=btnUpdate]").attr("rel", "delete");
                                  $("[id*=btnUpdate]").click();
                                  $(this).dialog('close');
                              },
                              cancel: function () {
                                  $(this).dialog("close");
                                  return false;
                              }
                          },
                          open: function () {
                              $('.ui-dialog-titlebar').find('button').remove();
                              $('.ui-dialog-buttonset').find('button').removeClass('ui-button ui-widget ui-state-default ui-corner-all ui-button-text-only ui-state-hover').addClass('btn btn-danger');
                          }
                      });
  
                      $(btnUpdate).click(function (e) {
                          if ($(this).attr("rel") != "delete") {
                              $('#dialogMedicalCategory').dialog('open');
                              return false;
                          } else {
                              __doPostBack(this.name, '');
                              //return true;
                          }
                      });
                  });
  
      &lt;asp:Button ID="btnUpdate" CssClass=" btn btn-success" runat="server" Style="display: none" Text="Update" OnClick="btnUpdate_Click" /&gt;
  </code></pre>
  
  <p>__doPostBack(this.name, ''); is not a function error was thrown, while click on ok button,while iam using in aspx page it will working fine but when i am using master page only it shown the error. i am suffering from this error on last 5 days please help me.</p>