LinkLabel.LinkArea LinkLabel.LinkArea LinkLabel.LinkArea LinkLabel.LinkArea Property

Definition

Gets or sets the range in the text to treat as a link.

public:
 property System::Windows::Forms::LinkArea LinkArea { System::Windows::Forms::LinkArea get(); void set(System::Windows::Forms::LinkArea value); };
public System.Windows.Forms.LinkArea LinkArea { get; set; }
member this.LinkArea : System.Windows.Forms.LinkArea with get, set
Public Property LinkArea As LinkArea

Property Value

A LinkArea that represents the area treated as a link.

Exceptions

The Start property of the LinkArea object is less than zero.

-or-

The Length property of the LinkArea object is less than -1.

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

The LinkArea property provides a quick way to specify a single hyperlink to display in the text of the LinkLabel control. The LinkArea object provides properties that specify the starting position of the link within the text of the control and the length of text for the hyperlink. When a hyperlink is specified using the LinkArea property, the hyperlink is added to the LinkLabel.LinkCollection of the control. The LinkArea property converts the LinkArea object assigned to it to a LinkLabel.Link object that is stored within the collection.

To add multiple hyperlinks to the text of the control, you can use the Links property. The Links property enables you to access the properties and methods of the LinkLabel.LinkCollection, which stores the links specified for the control. This method of adding links to the LinkLabel also enables you to specify data in the LinkData property that is associated with the link being created. The value of the LinkData property can be used to store the location of a file to display or the address of a Web site.

When a LinkLabel control is created, a default hyperlink that contains all the text within the LinkLabel control is added to the LinkLabel.LinkCollection. You can override this default link by specifying a new link area with the LinkArea property, or specify a link using the Add method of the LinkLabel.LinkCollection. You can also remove the default hyperlink by using the Remove method of the LinkLabel.LinkCollection class.

Note

The LinkArea property always returns the first item in the LinkLabel.LinkCollection, regardless of how the hyperlink was added to the collection.

Note

The Length property on LinkArea will differ if you call UseCompatibleTextRendering, and the Text property contains double-byte characters. If you call UseCompatibleTextRendering, it will return the number of bytes in the string. Otherwise, it will return the number of actual characters.

Applies to

See also