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LinkArea Structure

Represents an area within a LinkLabel control that represents a hyperlink within the control.

Namespace:  System.Windows.Forms
Assembly:  System.Windows.Forms (in System.Windows.Forms.dll)
[SerializableAttribute]
[TypeConverterAttribute(typeof(LinkArea..::..LinkAreaConverter))]
public struct LinkArea

The LinkArea type exposes the following members.

  Name Description
Public method LinkArea Initializes a new instance of the LinkArea class.
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  Name Description
Public property IsEmpty Gets a value indicating whether the LinkArea is empty.
Public property Length Gets or sets the number of characters in the link area.
Public property Start Gets or sets the starting location of the link area within the text of the LinkLabel.
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  Name Description
Public method Equals Determines whether this LinkArea is equal to the specified object. (Overrides ValueType.Equals(Object).)
Protected method Finalize Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.)
Public method GetHashCode Returns the hash code for this instance. (Overrides ValueType.GetHashCode().)
Public method GetType Gets the Type of the current instance. (Inherited from Object.)
Protected method MemberwiseClone Creates a shallow copy of the current Object. (Inherited from Object.)
Public method ToString Returns the fully qualified type name of this instance. (Overrides ValueType.ToString().)
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  Name Description
Public operator Static member Equality Returns a value indicating whether two instances of the LinkArea class are equal.
Public operator Static member Inequality Returns a value indicating whether two instances of the LinkArea class are not equal.
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There are two ways to add a hyperlink to the text of a LinkLabel control. You can access the Add method of the LinkLabel.LinkCollection class through the Links property of the LinkLabel to add multiple hyperlinks to the control's text. If you only need to add a single hyperlink to the text of the control, you can use the LinkArea property of the LinkLabel. This property accepts a LinkArea that defines the location of the hyperlink within the control's text. When a hyperlink is specified using the LinkArea property, the link area is then added to the LinkLabel.LinkCollection in the same manner as adding the link using the Add method of the LinkLabel.LinkCollection.

The Length property specifies the number of characters within the text of the LinkLabel to include in the link area. The Start property specifies the first character in the control text to include in the hyperlink. If you want to determine whether a specific LinkArea is empty, you can use the IsEmpty property instead of checking the values of the Start and Length properties.

The following code 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;
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);
        }
    }
}


.NET Framework

Supported in: 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.
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