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WebBrowserNavigatingEventHandler Delegate

  • Reference

Definition

Namespace:
System.Windows.Forms
Assembly:
System.Windows.Forms.dll

Represents the method that will handle the Navigating event of a WebBrowser control.

public delegate void WebBrowserNavigatingEventHandler(System::Object ^ sender, WebBrowserNavigatingEventArgs ^ e);
public delegate void WebBrowserNavigatingEventHandler(object sender, WebBrowserNavigatingEventArgs e);
public delegate void WebBrowserNavigatingEventHandler(object? sender, WebBrowserNavigatingEventArgs e);
type WebBrowserNavigatingEventHandler = delegate of obj * WebBrowserNavigatingEventArgs -> unit
Public Delegate Sub WebBrowserNavigatingEventHandler(sender As Object, e As WebBrowserNavigatingEventArgs)

Parameters

sender
Object

The source of the event.

e
WebBrowserNavigatingEventArgs

A WebBrowserNavigatingEventArgs that contains the event data.

Examples

The following code example demonstrates how to use a handler for the WebBrowser.Navigating event to cancel navigation when a Web page form has not been filled in. The WebBrowser.Document property is used to determine whether the form input field contains a value. This example requires that your form contains a WebBrowser control called webBrowser1.

private void Form1_Load(object sender, EventArgs e)
{
    webBrowser1.DocumentText =
        "<html><body>Please enter your name:<br/>" +
        "<input type='text' name='userName'/><br/>" +
        "<a href='http://www.microsoft.com'>continue</a>" +
        "</body></html>";
    webBrowser1.Navigating += 
        new WebBrowserNavigatingEventHandler(webBrowser1_Navigating);
}

private void webBrowser1_Navigating(object sender, 
    WebBrowserNavigatingEventArgs e)
{
    System.Windows.Forms.HtmlDocument document =
        this.webBrowser1.Document;

    if (document != null && document.All["userName"] != null && 
        String.IsNullOrEmpty(
        document.All["userName"].GetAttribute("value")))
    {
        e.Cancel = true;
        System.Windows.Forms.MessageBox.Show(
            "You must enter your name before you can navigate to " +
            e.Url.ToString());
    }
}

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

    webBrowser1.DocumentText = _
        "<html><body>Please enter your name:<br/>" & _
        "<input type='text' name='userName'/><br/>" & _
        "<a href='http://www.microsoft.com'>continue</a>" & _
        "</body></html>"

End Sub

Private Sub webBrowser1_Navigating( _
    ByVal sender As Object, ByVal e As WebBrowserNavigatingEventArgs) _
    Handles webBrowser1.Navigating

    Dim document As System.Windows.Forms.HtmlDocument = _
        webBrowser1.Document
    If document IsNot Nothing And _
        document.All("userName") IsNot Nothing And _
        String.IsNullOrEmpty( _
        document.All("userName").GetAttribute("value")) Then

        e.Cancel = True
        MsgBox("You must enter your name before you can navigate to " & _
            e.Url.ToString())
    End If

End Sub

Remarks

When you create a WebBrowserNavigatingEventHandler delegate, you identify the method that will handle the event. To associate the event with your event handler, add an instance of the delegate to the event. The event handler is called whenever the event occurs, unless you remove the delegate. For more information about event handler delegates, see Handling and Raising Events.

Extension Methods

GetMethodInfo(Delegate)

Gets an object that represents the method represented by the specified delegate.

Applies to

See also