Bundling JQuery in ASP.NET Web Forms 4.5

Question

I used Visual Studio 2012 and the built-in template (under Add -> New Project) to create a brand new ASP.NET Web Forms web application project. Inside the Site.Master page provided by default I see some markup targeting JQuery, which is included down below.

How does ASP.NET figure out the paths necessary to include JQuery, given the following mark up?

<asp:ScriptManager runat="server">
    <Scripts>
        <%--Framework Scripts--%>
        <asp:ScriptReference Name="MsAjaxBundle" />
        <asp:ScriptReference Name="jquery" />
        <asp:ScriptReference Name="jquery.ui.combined" />
        <asp:ScriptReference Name="WebForms.js" Assembly="System.Web" Path="~/Scripts/WebForms/WebForms.js" />
        <asp:ScriptReference Name="WebUIValidation.js" Assembly="System.Web" Path="~/Scripts/WebForms/WebUIValidation.js" />
        <asp:ScriptReference Name="MenuStandards.js" Assembly="System.Web" Path="~/Scripts/WebForms/MenuStandards.js" />
        <asp:ScriptReference Name="GridView.js" Assembly="System.Web" Path="~/Scripts/WebForms/GridView.js" />
        <asp:ScriptReference Name="DetailsView.js" Assembly="System.Web" Path="~/Scripts/WebForms/DetailsView.js" />
        <asp:ScriptReference Name="TreeView.js" Assembly="System.Web" Path="~/Scripts/WebForms/TreeView.js" />
        <asp:ScriptReference Name="WebParts.js" Assembly="System.Web" Path="~/Scripts/WebForms/WebParts.js" />
        <asp:ScriptReference Name="Focus.js" Assembly="System.Web" Path="~/Scripts/WebForms/Focus.js" />
        <asp:ScriptReference Name="WebFormsBundle" />
        <%--Site Scripts--%>
    </Scripts>
</asp:ScriptManager>

I don't see anywhere a config file or code that would resolve jquery to "~/Scripts/jquery-1.7.1.js". I see a packages.config file but it doesn't explicitly describe the path that must be being calculated somehow.

Does anyone know how the path to JQuery's javascript file is resolved at runtime?

Answer 1

Inside the Microsoft.ScriptManager.WebForms PreAppStartCode, it has:

        System.Web.UI.ScriptManager.ScriptResourceMapping.AddDefinition("WebFormsBundle", new ScriptResourceDefinition
        {
            Path = "~/bundles/WebFormsJs",
            CdnPath = "http://ajax.aspnetcdn.com/ajax/4.5/6/WebFormsBundle.js",
            LoadSuccessExpression="window.WebForm_PostBackOptions",
            CdnSupportsSecureConnection = true
        });

This is what hooks up to the declarations from the script reference:

<asp:ScriptReference Name="WebFormsBundle" />

And also does the deduplication because the ScriptReference path is the same as the path for the files inside of your bundle which should be registered inside of BundleConfig.cs