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SplitContainer.Dock Property

Gets or sets which SplitContainer borders are attached to the edges of the container.

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

public DockStyle Dock { get; set; }

Property Value

Type: System.Windows.Forms.DockStyle
One of the DockStyle values. The default value is None.

You can dock a SplitContainer to any edge of its container, or you can dock a SplitContainer to all edges of the container so that the SplitContainer entirely fills the container. For example, set this property to DockStyle.Left to attach the left edge of the SplitContainer to the left edge of its container. Controls are docked in z-order.


The z-order corresponds to the depth dimension of the screen, and the x-order and y-order corresponds to the horizontal and vertical dimensions, respectively. Z-order defines which object appears in front of which, in cases where controls or windows can overlap or occupy the same space on the screen. A control or window at the top of the z-order appears on top of all other controls or windows and is referenced by an index of 0 in the Controls property. A control or window at the bottom of the z-order appears underneath all other controls or windows and is referenced by an index of (Controls.Count-1) in the Controls property.

For more information about anchoring and docking controls, see How to: Create a Multipane User Interface with Windows Forms.

The following code example shows a vertical splitter whose Dock property is set to Fill. Other basic properties of a vertical splitter are also shown. This example is part of a larger example provided for the SplitContainer class.

        // Basic SplitContainer properties.
        // This is a vertical splitter that moves in 10-pixel increments.
        // This splitter needs no explicit Orientation property because Vertical is the default.
        splitContainer1.Dock = System.Windows.Forms.DockStyle.Fill;
        splitContainer1.ForeColor = System.Drawing.SystemColors.Control;
        splitContainer1.Location = new System.Drawing.Point(0, 0);
        splitContainer1.Name = "splitContainer1";
        // You can drag the splitter no nearer than 30 pixels from the left edge of the container.
        splitContainer1.Panel1MinSize = 30;
        // You can drag the splitter no nearer than 20 pixels from the right edge of the container.
        splitContainer1.Panel2MinSize = 20;
        splitContainer1.Size = new System.Drawing.Size(292, 273);
        splitContainer1.SplitterDistance = 79;
        // This splitter moves in 10-pixel increments.
        splitContainer1.SplitterIncrement = 10;
        splitContainer1.SplitterWidth = 6;
        // splitContainer1 is the first control in the tab order.
        splitContainer1.TabIndex = 0;
        splitContainer1.Text = "splitContainer1";
        // When the splitter moves, the cursor changes shape.
        splitContainer1.SplitterMoved += new System.Windows.Forms.SplitterEventHandler(splitContainer1_SplitterMoved);
        splitContainer1.SplitterMoving += new System.Windows.Forms.SplitterCancelEventHandler(splitContainer1_SplitterMoving);

        // Add a TreeView control to the left panel.
        splitContainer1.Panel1.BackColor = System.Drawing.SystemColors.Control;
        // Add a TreeView control to Panel1.
        splitContainer1.Panel1.Name = "splitterPanel1";
        // Controls placed on Panel1 support right-to-left fonts.
        splitContainer1.Panel1.RightToLeft = System.Windows.Forms.RightToLeft.Yes;

.NET Framework

Supported in: 4, 3.5, 3.0, 2.0

.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.