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How to: Reference ASP.NET Master Page Content

You can write code in content pages that references properties, methods, and controls in the master page, with some restrictions. The rule for properties and methods is that you can reference them if they are declared as public members of the master page. This includes public properties and public methods. You can reference controls on the master page independently of referencing public members.

A Visual Studio project with source code is available to accompany this topic: Download.

To reference a public member on the master page

  1. Add a @ MasterType directive in the content page. In the directive, set the VirtualPath attribute to the location of the master page, as in this example:

    <%@ MasterType virtualpath="~/Masters/Master1.master" %>

    This directive causes the content page's Master property to be strongly typed.

  2. Write code that uses the master page's public member as a member of the Master property, as in this example, which assigns the value of a public property named CompanyName from the master page to a text box on the content page:

    CompanyName.Text = Master.CompanyName
    CompanyName.Text = Master.CompanyName;

To reference a control on the master page

  • Use the FindControl method, using the value returned by the Master property as the naming container.

    The following code example shows how to use the FindControl method to get a reference to two controls on the master page, a TextBox control and a Label control. Because the TextBox control is inside a ContentPlaceHolder control, you must first get a reference to the ContentPlaceHolder and then use its FindControl method to locate the TextBox control.

    Sub Page_Load()
        Dim mpContentPlaceHolder As ContentPlaceHolder
        Dim mpTextBox As TextBox
        mpContentPlaceHolder = _
            CType(Master.FindControl("ContentPlaceHolder1"), _
        If Not mpContentPlaceHolder Is Nothing Then
            mpTextBox = CType(mpContentPlaceHolder. _
                FindControl("TextBox1"), TextBox)
            If Not mpTextBox Is Nothing Then
                mpTextBox.Text = "TextBox found!"
            End If
        End If
        ' Gets a reference to a Label control not in a 
        ' ContentPlaceHolder
        Dim mpLabel As Label
        mpLabel = CType(Master.FindControl("masterPageLabel"), Label)
        If Not mpLabel Is Nothing Then
            Label1.Text = "Master page label = " + mpLabel.Text
        End If
    End Sub
    void Page_Load()
        // Gets a reference to a TextBox control inside 
        // a ContentPlaceHolder
        ContentPlaceHolder mpContentPlaceHolder;
        TextBox mpTextBox;
        mpContentPlaceHolder = 
        if(mpContentPlaceHolder != null)
            mpTextBox = 
                (TextBox) mpContentPlaceHolder.FindControl("TextBox1");
            if(mpTextBox != null)
                mpTextBox.Text = "TextBox found!";
        // Gets a reference to a Label control that not in 
        // a ContentPlaceHolder
        Label mpLabel = (Label) Master.FindControl("masterPageLabel");
        if(mpLabel != null)
            Label1.Text = "Master page label = " + mpLabel.Text;

See Also


Working with ASP.NET Master Pages Programmatically

Other Resources

ASP.NET Master Pages

Accessing ASP.NET Controls Programmatically