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CheckedListBox.SelectionMode Property

Gets or sets a value specifying the selection mode.

Namespace: System.Windows.Forms
Assembly: System.Windows.Forms (in

public override SelectionMode SelectionMode { get; set; }
/** @property */
public SelectionMode get_SelectionMode ()

/** @property */
public void set_SelectionMode (SelectionMode value)

public override function get SelectionMode () : SelectionMode

public override function set SelectionMode (value : SelectionMode)

Property Value

Either the One or None value of System.Windows.Forms.SelectionMode.

Exception typeCondition


An attempt was made to assign a value that is not a System.Windows.Forms.SelectionMode value of One or None.


An attempt was made to assign the MultiExtended value of System.Windows.Forms.SelectionMode to the control.

For CheckedListBox objects, multiple selection is not supported. You can set the mode to one item or no items.

The following code example demonstrates initializing a CheckedListBox control by setting the CheckOnClick, SelectionMode, and ThreeDCheckBoxes properties. The example populates the CheckedListBox with controls and sets the DisplayMember to the Control.Name property of the control.

To run the example, paste the following code in a form containing a CheckedListBox named CheckedListBox1 and call the InitializeCheckListBox method from the form's constructor or Load method.

// This method initializes CheckedListBox1 with a list of all 
// the controls on the form. It sets the selection mode
// to single selection and allows selection with a single click.
// It adds itself to the list before adding itself to the form.

internal System.Windows.Forms.CheckedListBox CheckedListBox1;

private void InitializeCheckedListBox()
    this.CheckedListBox1 = new CheckedListBox();
    this.CheckedListBox1.Location = new System.Drawing.Point(40, 90);
    this.CheckedListBox1.CheckOnClick = true;
    this.CheckedListBox1.Name = "CheckedListBox1";
    this.CheckedListBox1.Size = new System.Drawing.Size(120, 94);
    this.CheckedListBox1.TabIndex = 1;
    this.CheckedListBox1.SelectionMode = SelectionMode.One;
    this.CheckedListBox1.ThreeDCheckBoxes = true;

    foreach ( Control aControl in this.Controls )
        this.CheckedListBox1.Items.Add(aControl, false);

    this.CheckedListBox1.DisplayMember = "Name";

Windows 98, Windows 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see System Requirements.

.NET Framework

Supported in: 2.0, 1.1, 1.0