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LinkLabel.Link.Visited Property

Definition

Gets or sets a value indicating whether the user has visited the link.

public:
 property bool Visited { bool get(); void set(bool value); };
public bool Visited { get; set; }
member this.Visited : bool with get, set
Public Property Visited As Boolean

Property Value

true if the link has been visited; otherwise, false.

Examples

The following example demonstrates using the LinkLabel class, with multiple LinkArea sections defined, to display a label on a form. The example demonstrates setting the AutoSize, LinkBehavior, DisabledLinkColor, LinkColor, and VisitedLinkColor properties to customize the look of the LinkLabel. The first LinkArea is specified using the LinkLabel.LinkArea property. Additional links are added to the LinkLabel using the LinkLabel.LinkCollection.Add method. The example handles the LinkClicked event by starting the Web browser for hyperlinks, and displaying a MessageBox for other links.

#using <System.dll>
#using <System.Windows.Forms.dll>
#using <System.Drawing.dll>

using namespace System;
using namespace System::Drawing;
using namespace System::Windows::Forms;
public ref class Form1: public System::Windows::Forms::Form
{
private:
   System::Windows::Forms::LinkLabel^ linkLabel1;

public:
   Form1()
   {
      
      // Create the LinkLabel.
      this->linkLabel1 = gcnew System::Windows::Forms::LinkLabel;
      
      // Configure the LinkLabel's size and location. Specify that the
      // size should be automatically determined by the content.
      this->linkLabel1->Location = System::Drawing::Point( 34, 56 );
      this->linkLabel1->Size = System::Drawing::Size( 224, 16 );
      this->linkLabel1->AutoSize = true;
      
      // Configure the appearance.
      this->linkLabel1->DisabledLinkColor = System::Drawing::Color::Red;
      this->linkLabel1->VisitedLinkColor = System::Drawing::Color::Blue;
      this->linkLabel1->LinkBehavior = System::Windows::Forms::LinkBehavior::HoverUnderline;
      this->linkLabel1->LinkColor = System::Drawing::Color::Navy;
      this->linkLabel1->TabIndex = 0;
      this->linkLabel1->TabStop = true;
      
      // Add an event handler to do something when the links are clicked.
      this->linkLabel1->LinkClicked += gcnew System::Windows::Forms::LinkLabelLinkClickedEventHandler( this, &Form1::linkLabel1_LinkClicked );
      
      // Identify what the first Link is.
      this->linkLabel1->LinkArea = System::Windows::Forms::LinkArea( 0, 8 );
      
      // Identify that the first link is visited already.
      this->linkLabel1->Links[ 0 ]->Visited = true;
      
      // Set the Text property to a String*.
      this->linkLabel1->Text = "Register Online.  Visit Microsoft.  Visit MSN.";
      
      // Create new links using the Add method of the LinkCollection class.
      // Underline the appropriate words in the LinkLabel's Text property.
      // The words 'Register', 'Microsoft', and 'MSN' will
      // all be underlined and behave as hyperlinks.
      // First check that the Text property is long enough to accommodate
      // the desired hyperlinked areas.  If it's not, don't add hyperlinks.
      if ( this->linkLabel1->Text->Length >= 45 )
      {
         this->linkLabel1->Links[ 0 ]->LinkData = "Register";
         this->linkLabel1->Links->Add( 24, 9, "www.microsoft.com" );
         this->linkLabel1->Links->Add( 42, 3, "www.msn.com" );
         this->linkLabel1->Links[ 1 ]->Enabled = false;
      }

      
      // Set up how the form should be displayed and add the controls to the form.
      this->ClientSize = System::Drawing::Size( 292, 266 );
      array<System::Windows::Forms::Control^>^temp0 = {this->linkLabel1};
      this->Controls->AddRange( temp0 );
      this->Text = "Link Label Example";
   }


private:
   void linkLabel1_LinkClicked( Object^ /*sender*/, System::Windows::Forms::LinkLabelLinkClickedEventArgs^ e )
   {
      // Determine which link was clicked within the LinkLabel.
      this->linkLabel1->Links[ linkLabel1->Links->IndexOf( e->Link ) ]->Visited = true;
      
      // Display the appropriate link based on the value of the
      // LinkData property of the Link Object*.
      String^ target = dynamic_cast<String^>(e->Link->LinkData);
      
      // If the value looks like a URL, navigate to it.
      // Otherwise, display it in a message box.
      if ( nullptr != target && target->StartsWith( "www" ) )
      {
         System::Diagnostics::Process::Start( target );
      }
      else
      {
         MessageBox::Show( "Item clicked: {0}", target );
      }
   }
};

[STAThread]
int main()
{
   Application::Run( gcnew Form1 );
}
using System;
using System.Drawing;
using System.Windows.Forms;

public class Form1 : System.Windows.Forms.Form
{
    private System.Windows.Forms.LinkLabel linkLabel1;
    
    [STAThread]
    static void Main() 
    {
        Application.Run(new Form1());
    }

    public Form1()
    {
        // Create the LinkLabel.
        this.linkLabel1 = new System.Windows.Forms.LinkLabel();

        // Configure the LinkLabel's size and location. Specify that the
        // size should be automatically determined by the content.
        this.linkLabel1.Location = new System.Drawing.Point(34, 56);
        this.linkLabel1.Size = new System.Drawing.Size(224, 16);
        this.linkLabel1.AutoSize = true;

        // Configure the appearance. 
        // Set the DisabledLinkColor so that a disabled link will show up against the form's background.
        this.linkLabel1.DisabledLinkColor = System.Drawing.Color.Red;
        this.linkLabel1.VisitedLinkColor = System.Drawing.Color.Blue;
        this.linkLabel1.LinkBehavior = System.Windows.Forms.LinkBehavior.HoverUnderline;
        this.linkLabel1.LinkColor = System.Drawing.Color.Navy;
        
        this.linkLabel1.TabIndex = 0;
        this.linkLabel1.TabStop = true;

        // Add an event handler to do something when the links are clicked.
        this.linkLabel1.LinkClicked += new System.Windows.Forms.LinkLabelLinkClickedEventHandler(this.linkLabel1_LinkClicked);

        // Identify what the first Link is.
        this.linkLabel1.LinkArea = new System.Windows.Forms.LinkArea(0, 8);

        // Identify that the first link is visited already.
        this.linkLabel1.Links[0].Visited = true;
        
        // Set the Text property to a string.
        this.linkLabel1.Text = "Register Online.  Visit Microsoft.  Visit MSN.";

        // Create new links using the Add method of the LinkCollection class.
        // Underline the appropriate words in the LinkLabel's Text property.
        // The words 'Register', 'Microsoft', and 'MSN' will 
        // all be underlined and behave as hyperlinks.

        // First check that the Text property is long enough to accommodate
        // the desired hyperlinked areas.  If it's not, don't add hyperlinks.
        if(this.linkLabel1.Text.Length >= 45)
        {
            this.linkLabel1.Links[0].LinkData = "Register";
            this.linkLabel1.Links.Add(24, 9, "www.microsoft.com");
            this.linkLabel1.Links.Add(42, 3, "www.msn.com");
        //  The second link is disabled and will appear as red.
            this.linkLabel1.Links[1].Enabled = false;
        }
        
        // Set up how the form should be displayed and add the controls to the form.
        this.ClientSize = new System.Drawing.Size(292, 266);
        this.Controls.AddRange(new System.Windows.Forms.Control[] {this.linkLabel1});
        this.Text = "Link Label Example";
    }

    private void linkLabel1_LinkClicked(object sender, System.Windows.Forms.LinkLabelLinkClickedEventArgs e)
    {
        // Determine which link was clicked within the LinkLabel.
        this.linkLabel1.Links[linkLabel1.Links.IndexOf(e.Link)].Visited = true;

        // Display the appropriate link based on the value of the 
        // LinkData property of the Link object.
        string target = e.Link.LinkData as string;

        // If the value looks like a URL, navigate to it.
        // Otherwise, display it in a message box.
        if(null != target && target.StartsWith("www"))
        {
            System.Diagnostics.Process.Start(target);
        }
        else
        {    
            MessageBox.Show("Item clicked: " + target);
        }
    }
}
Imports System.Drawing
Imports System.Windows.Forms

Public NotInheritable Class Form1
    Inherits System.Windows.Forms.Form

    Friend WithEvents LinkLabel1 As System.Windows.Forms.LinkLabel

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

    Public Sub New()
        MyBase.New()


        Me.LinkLabel1 = New System.Windows.Forms.LinkLabel

        ' Configure the LinkLabel's size and location. Specify that the
        ' size should be automatically determined by the content.
        Me.linkLabel1.Location = New System.Drawing.Point(34, 56) 
        Me.linkLabel1.Size = New System.Drawing.Size(224, 16) 
        Me.linkLabel1.AutoSize = True 

        ' Configure the appearance.
        ' Set the DisabledLinkColor so that a disabled link will show up against the form's background.
        Me.linkLabel1.DisabledLinkColor = System.Drawing.Color.Red 
        Me.linkLabel1.VisitedLinkColor = System.Drawing.Color.Blue 
        Me.linkLabel1.LinkBehavior = System.Windows.Forms.LinkBehavior.HoverUnderline 
        Me.linkLabel1.LinkColor = System.Drawing.Color.Navy 
        
        Me.linkLabel1.TabIndex = 0 
        Me.linkLabel1.TabStop = True 
        
        ' Identify what the first Link is.
        Me.linkLabel1.LinkArea = New System.Windows.Forms.LinkArea(0, 8)

        ' Identify that the first link is visited already.
        Me.linkLabel1.Links(0).Visited = true
        
        ' Set the Text property to a string.
        Me.linkLabel1.Text = "Register Online.  Visit Microsoft.  Visit MSN."

        ' Create new links using the Add method of the LinkCollection class.
        ' Underline the appropriate words in the LinkLabel's Text property.
        ' The words 'Register', 'Microsoft', and 'MSN' will 
        ' all be underlined and behave as hyperlinks.

        ' First check that the Text property is long enough to accommodate
        ' the desired hyperlinked areas.  If it's not, don't add hyperlinks.
        If Me.LinkLabel1.Text.Length >= 45 Then
            Me.LinkLabel1.Links(0).LinkData = "Register"
            Me.LinkLabel1.Links.Add(24, 9, "www.microsoft.com")
            Me.LinkLabel1.Links.Add(42, 3, "www.msn.com")
            ' The second link is disabled and will appear as red.
            Me.linkLabel1.Links(1).Enabled = False
        End If

        ' Set up how the form should be displayed and adds the controls to the form.
        Me.ClientSize = New System.Drawing.Size(292, 266)
        Me.Controls.AddRange(New System.Windows.Forms.Control() {Me.LinkLabel1})
        Me.Text = "Link Label Example"
    End Sub

    Private Sub linkLabel1_LinkClicked(ByVal sender As Object, _
                ByVal e As System.Windows.Forms.LinkLabelLinkClickedEventArgs) Handles LinkLabel1.LinkClicked

        ' Determine which link was clicked within the LinkLabel.
        Me.LinkLabel1.Links(LinkLabel1.Links.IndexOf(e.Link)).Visited = True

        ' Displays the appropriate link based on the value of the LinkData property of the Link object.
        Dim target As String = CType(e.Link.LinkData, String)

        ' If the value looks like a URL, navigate to it.
        ' Otherwise, display it in a message box.
        If (target IsNot Nothing) AndAlso (target.StartsWith("www")) Then
            System.Diagnostics.Process.Start(target)
        Else
            MessageBox.Show(("Item clicked: " + target))
        End If

    End Sub

End Class

Remarks

A LinkLabel control does not automatically denote that a link is a visited link. To display the link as a visited link, you can set the value of this property to true in an event handler for the LinkClicked event of a LinkLabel. A visited link is displayed using the color specified in the VisitedLinkColor property of the LinkLabel control. Once the form containing the LinkLabel control is closed, the all display state associated with the link is deleted. In order to retain the display state of the link, you need to store the display state of the link in a registry setting associated with your application.

Note

If you have only one link specified in a LinkLabel control, you can use the LinkVisited property of the LinkLabel to specify the link as visited. You can also use the LinkVisited property if you have multiple links defined, but the setting only applies to the first link defined in the control.

Applies to

See also