ScrollBar.Maximum Property


Gets or sets the upper limit of values of the scrollable range.

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

public int Maximum { get; set; }

Property Value

Type: System.Int32

A numeric value. The default value is 100.

You might consider adjusting the Maximum property dynamically to match the size of the scroll bar's parent in proportion to pixel size or to the number of rows or lines displayed.

The maximum value can only be reached programmatically. The value of a scroll bar cannot reach its maximum value through user interaction at run time. The maximum value that can be reached through user interaction is equal to 1 plus the Maximum property value minus the LargeChange property value. If necessary, you can set the Maximum property to the size of the object -1 to account for the term of 1.

The following example assumes that you have created a Form, added a PictureBox to the Form, and added a horizontal HScrollBar and a vertical VScrollBar to the PictureBox. This code example is part of a larger example provided for the ScrollBar class overview.

In this example, the Maximum property is set to the size of the Image plus the size of the scrollbar if it is visible plus an adjustment factor of the size of the LargeChange property.

You must add references to the System.Drawing and System.Windows.Forms namespaces to run this example.


For instructions about how to run this example in Visual Studio, see How to: Compile and Run a Complete Windows Forms Code Example Using Visual Studio.

public void SetScrollBarValues()
    //Set the following scrollbar properties:

    //Minimum: Set to 0

    //SmallChange and LargeChange: Per UI guidelines, these must be set
    //    relative to the size of the view that the user sees, not to
    //    the total size including the unseen part.  In this example,
    //    these must be set relative to the picture box, not to the image.

    //Maximum: Calculate in steps:
    //Step 1: The maximum to scroll is the size of the unseen part.
    //Step 2: Add the size of visible scrollbars if necessary.
    //Step 3: Add an adjustment factor of ScrollBar.LargeChange.

    //Configure the horizontal scrollbar
    if (this.hScrollBar1.Visible)
        this.hScrollBar1.Minimum = 0;
        this.hScrollBar1.SmallChange = this.pictureBox1.Width / 20;
        this.hScrollBar1.LargeChange = this.pictureBox1.Width / 10;

        this.hScrollBar1.Maximum = this.pictureBox1.Image.Size.Width - pictureBox1.ClientSize.Width;  //step 1

        if (this.vScrollBar1.Visible) //step 2
            this.hScrollBar1.Maximum += this.vScrollBar1.Width;

        this.hScrollBar1.Maximum += this.hScrollBar1.LargeChange; //step 3

    //Configure the vertical scrollbar
    if (this.vScrollBar1.Visible)
        this.vScrollBar1.Minimum = 0;
        this.vScrollBar1.SmallChange = this.pictureBox1.Height / 20;
        this.vScrollBar1.LargeChange = this.pictureBox1.Height / 10;

        this.vScrollBar1.Maximum = this.pictureBox1.Image.Size.Height - pictureBox1.ClientSize.Height; //step 1

        if (this.hScrollBar1.Visible) //step 2
            this.vScrollBar1.Maximum += this.hScrollBar1.Height;

        this.vScrollBar1.Maximum += this.vScrollBar1.LargeChange; //step 3

.NET Framework
Available since 1.1
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