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LinkLabel.LinkArea Proprietà

Definizione

Ottiene o imposta l’intervallo nel testo da trattare come collegamento.

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

Valore della proprietà

LinkArea che rappresenta l'area trattata come collegamento.

Eccezioni

La proprietà Start dell'oggetto LinkArea è minore di 0.

-oppure-

La proprietà Length dell'oggetto LinkArea è minore di -1.

Esempio

Nell'esempio seguente viene illustrato l'uso della LinkLabel classe , con più LinkArea sezioni definite, per visualizzare un'etichetta in un modulo. Nell'esempio viene illustrata l'impostazione delle AutoSizeproprietà , LinkBehavior, DisabledLinkColorLinkColor, e VisitedLinkColor per personalizzare l'aspetto di LinkLabel. Il primo LinkArea viene specificato utilizzando la LinkLabel.LinkArea proprietà . I collegamenti aggiuntivi vengono aggiunti all'oggetto LinkLabel utilizzando il LinkLabel.LinkCollection.Add metodo . Nell'esempio viene gestito l'evento LinkClicked avviando il Web browser per i collegamenti ipertestuali e visualizzando un MessageBox oggetto per altri collegamenti.

#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

Commenti

La LinkArea proprietà consente di specificare rapidamente un singolo collegamento ipertestuale da visualizzare nel testo del LinkLabel controllo. L'oggetto LinkArea fornisce proprietà che specificano la posizione iniziale del collegamento all'interno del testo del controllo e la lunghezza del testo per il collegamento ipertestuale. Quando si specifica un collegamento ipertestuale utilizzando la LinkArea proprietà , il collegamento ipertestuale viene aggiunto al LinkLabel.LinkCollection del controllo . La LinkArea proprietà converte l'oggetto LinkArea assegnato a esso in un LinkLabel.Link oggetto archiviato all'interno dell'insieme.

Per aggiungere più collegamenti ipertestuali al testo del controllo, è possibile utilizzare la Links proprietà . La Links proprietà consente di accedere alle proprietà e ai metodi di LinkLabel.LinkCollection, che archivia i collegamenti specificati per il controllo . Questo metodo di aggiunta di collegamenti a LinkLabel consente anche di specificare i dati nella LinkData proprietà associata al collegamento creato. Il valore della LinkData proprietà può essere utilizzato per archiviare il percorso di un file da visualizzare o l'indirizzo di un sito Web.

Quando viene creato un LinkLabel controllo, al controllo LinkLabel.LinkCollectionviene aggiunto un collegamento ipertestuale predefinito contenente tutto il testo all'interno del LinkLabel controllo . È possibile eseguire l'override di questo collegamento predefinito specificando una nuova area di collegamento con la LinkArea proprietà oppure specificando un collegamento usando il Add metodo di LinkLabel.LinkCollection. È anche possibile rimuovere il collegamento ipertestuale predefinito usando il Remove metodo della LinkLabel.LinkCollection classe .

Nota

La LinkArea proprietà restituisce sempre il primo elemento dell'oggetto LinkLabel.LinkCollection, indipendentemente dal modo in cui il collegamento ipertestuale è stato aggiunto all'insieme.

Nota

La Length proprietà su LinkArea sarà diversa se si chiama UseCompatibleTextRenderinge la Text proprietà contiene caratteri a byte doppio. Se si chiama UseCompatibleTextRendering, restituirà il numero di byte nella stringa. In caso contrario, restituirà il numero di caratteri effettivi.

Si applica a

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