WebBrowser.ObjectForScripting Property

 

Gets or sets an object that can be accessed by scripting code that is contained within a Web page displayed in the WebBrowser control.

Namespace:   System.Windows.Forms
Assembly:  System.Windows.Forms (in System.Windows.Forms.dll)

<BrowsableAttribute(False)>
Public Property ObjectForScripting As Object

Property Value

Type: System.Object

The object being made available to the scripting code.

Exception Condition
ArgumentException

The specified value when setting this property is an instance of a non-public type.

-or-

The specified value when setting this property is an instance of a type that is not COM-visible. For more information, see Marshal.IsTypeVisibleFromCom.

Use this property to enable communication between a Web page hosted by the WebBrowser control and the application that contains the WebBrowser control. This property lets you integrate dynamic HTML (DHTML) code with your client application code. The object specified for this property is available to Web page script as the window.external object, which is a built-in DOM object provided for host access.

You can set this property to any COM-visible object for which you want its public properties and methods available to scripting code. You can make a class COM-visible by marking it with the ComVisibleAttribute.

To call functions defined in your Web page from your client application code, use the HtmlDocument.InvokeScript method of the HtmlDocument object you can retrieve from the Document property.

The following code example demonstrates how to use the ObjectForScripting property. In the example, the ObjectForScripting property is set to the current form.

Imports System
Imports System.Windows.Forms
Imports System.Security.Permissions

<PermissionSet(SecurityAction.Demand, Name:="FullTrust")> _
<System.Runtime.InteropServices.ComVisibleAttribute(True)> _
Public Class Form1
    Inherits Form

    Private webBrowser1 As New WebBrowser()
    Private WithEvents button1 As New Button()

    <STAThread()> _
    Public Shared Sub Main()
        Application.EnableVisualStyles()
        Application.Run(New Form1())
    End Sub

    Public Sub New()
        button1.Text = "call script code from client code"
        button1.Dock = DockStyle.Top
        webBrowser1.Dock = DockStyle.Fill
        Controls.Add(webBrowser1)
        Controls.Add(button1)
    End Sub

    Private Sub Form1_Load(ByVal sender As Object, ByVal e As EventArgs) _
        Handles Me.Load

        webBrowser1.AllowWebBrowserDrop = False
        webBrowser1.IsWebBrowserContextMenuEnabled = False
        webBrowser1.WebBrowserShortcutsEnabled = False
        webBrowser1.ObjectForScripting = Me
        ' Uncomment the following line when you are finished debugging.
        'webBrowser1.ScriptErrorsSuppressed = True

        webBrowser1.DocumentText = _
            "<html><head><script>" & _
            "function test(message) { alert(message); }" & _
            "</script></head><body><button " & _
            "onclick=""window.external.Test('called from script code')"" > " & _
            "call client code from script code</button>" & _
            "</body></html>"
    End Sub

    Public Sub Test(ByVal message As String)
        MessageBox.Show(message, "client code")
    End Sub

    Private Sub button1_Click(ByVal sender As Object, ByVal e As EventArgs) _
        Handles button1.Click

        webBrowser1.Document.InvokeScript("test", _
            New String() {"called from client code"})

    End Sub

End Class

SecurityPermission

for immediate callers to use this control. Demand value: LinkDemand; NIB: Named Permission Sets: FullTrust.

.NET Framework
Available since 2.0
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