title: jquery usage in asp.net mvc 4 _Layout.cshtml
body: <p>I used jquery in my asp.net mvc 4 project. The jquery code is in _Layout,cshtml. In IE 9, an exception was thrown.</p>
  
  <pre><code>Unhandled exception at line 14, column 9 in http://localhost:59899/
  0x800a1391 - Microsoft JScript runtime error: 'jQuery' is undefined
  </code></pre>
  
  <p>In firefox, no error was thrown but jquery didn't work at all.</p>
  
  <pre><code>&lt;!DOCTYPE html&gt;
  &lt;html lang="en"&gt;
  &lt;head&gt;
     &lt;meta charset="utf-8" /&gt;
     &lt;title&gt;@ViewBag.Title&lt;/title&gt;
     &lt;link href="~/favicon.ico" rel="shortcut icon" type="image/x-icon" /&gt;
     &lt;meta name="viewport" content="width=device-width" /&gt;
     @Styles.Render("~/Content/css")
     @Scripts.Render("~/bundles/modernizr")
  
  &lt;script type="text/javascript"&gt;
      jQuery(document).ready(function () {
          var divone = jQuery(".main-content").height();
          var divtwo = jQuery(".sidebar").height();
          var maxdiv = Math.max(divone, divtwo);
          jQuery(".main-content").height(maxdiv);
          jQuery(".sidebar").height(maxdiv);
      });
  &lt;/script&gt;
  </code></pre>
  
  <p></p>
  
  <p><strong>UPDATE:</strong></p>
  
  <p>In App_Start there is a BundleConfig.cs.</p>
  
  <pre><code>   public class BundleConfig
     {
      // For more information on Bundling, visit http://go.microsoft.com/fwlink/?LinkId=254725
      public static void RegisterBundles(BundleCollection bundles)
      {
          bundles.Add(new ScriptBundle("~/bundles/jquery").Include(
                      "~/Scripts/jquery-{version}.js"));
  
          bundles.Add(new ScriptBundle("~/bundles/jqueryui").Include(
                      "~/Scripts/jquery-ui-{version}.js"));
  
          bundles.Add(new ScriptBundle("~/bundles/jqueryval").Include(
                      "~/Scripts/jquery.unobtrusive*",
                      "~/Scripts/jquery.validate*"));
  
          // Use the development version of Modernizr to develop with and learn from. Then, when you're
          // ready for production, use the build tool at http://modernizr.com to pick only the tests you need.
          bundles.Add(new ScriptBundle("~/bundles/modernizr").Include(
                      "~/Scripts/modernizr-*"));
  
          bundles.Add(new StyleBundle("~/Content/css").Include("~/Content/site.css"));
  
          bundles.Add(new StyleBundle("~/Content/themes/base/css").Include(
                      "~/Content/themes/base/jquery.ui.core.css",
                      "~/Content/themes/base/jquery.ui.resizable.css",
                      "~/Content/themes/base/jquery.ui.selectable.css",
                      "~/Content/themes/base/jquery.ui.accordion.css",
                      "~/Content/themes/base/jquery.ui.autocomplete.css",
                      "~/Content/themes/base/jquery.ui.button.css",
                      "~/Content/themes/base/jquery.ui.dialog.css",
                      "~/Content/themes/base/jquery.ui.slider.css",
                      "~/Content/themes/base/jquery.ui.tabs.css",
                      "~/Content/themes/base/jquery.ui.datepicker.css",
                      "~/Content/themes/base/jquery.ui.progressbar.css",
                      "~/Content/themes/base/jquery.ui.theme.css"));
      }
  }
  </code></pre>