ScrollBar.LargeChange 屬性

定義

命名空間:

System.Windows.Forms

組件:

System.Windows.Forms.dll

來源:

ScrollBar.cs

當滾動框移動較遠距離時，會取得或設定一個值，要從屬性中加入或減 Value 去。

public:
 property int LargeChange { int get(); void set(int value); };

public int LargeChange { get; set; }

member this.LargeChange : int with get, set

Public Property LargeChange As Integer

屬性值

Int32

數值。 預設值為 10。

例外狀況

ArgumentOutOfRangeException

分配值小於 0。

範例

以下範例假設你已建立 Form，將 a 加入 FormPictureBox ，並在 中加入HScrollBar水平與垂直。VScrollBarPictureBox 這個程式碼範例是為類別概述提供 ScrollBar 的完整範例的一部分。

在此範例中， LargeChange 性質相對於 的 PictureBox大小設定。

執行此範例時，您必須為 和 的命名空間加入參考System.DrawingSystem.Windows.Forms。

備註

關於如何在 Visual Studio 中執行此範例的說明，請參見 《如何編譯並執行完整的 Windows 表單程式碼範例，使用 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
    }
}

Public Sub 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 (Me.hScrollBar1.Visible) Then

        Me.hScrollBar1.Minimum = 0
        Me.hScrollBar1.SmallChange = CInt(Me.pictureBox1.Width / 20)
        Me.hScrollBar1.LargeChange = CInt(Me.pictureBox1.Width / 10)

        Me.hScrollBar1.Maximum = Me.pictureBox1.Image.Size.Width - pictureBox1.ClientSize.Width  'step 1

        If (Me.vScrollBar1.Visible) Then 'step 2

            Me.hScrollBar1.Maximum += Me.vScrollBar1.Width
        End If

        Me.hScrollBar1.Maximum += Me.hScrollBar1.LargeChange 'step 3
    End If

    'Configure the vertical scrollbar
    '---------------------------------------------
    If (Me.vScrollBar1.Visible) Then

        Me.vScrollBar1.Minimum = 0
        Me.vScrollBar1.SmallChange = CInt(Me.pictureBox1.Height / 20)
        Me.vScrollBar1.LargeChange = CInt(Me.pictureBox1.Height / 10)

        Me.vScrollBar1.Maximum = Me.pictureBox1.Image.Size.Height - pictureBox1.ClientSize.Height 'step 1

        If (Me.hScrollBar1.Visible) Then 'step 2

            Me.vScrollBar1.Maximum += Me.hScrollBar1.Height
        End If

        Me.vScrollBar1.Maximum += Me.vScrollBar1.LargeChange 'step 3
    End If
 End Sub

備註

當使用者點擊滾動條軌道中滾動框兩側時， Value 屬性會根據屬性 LargeChange 設定的值改變。

備註

你可以處理按鍵事件，當使用者按下 PAGE Up 或 PAGE DOWN 鍵時，滾動框會移動。

使用者介面指引建議 和 LargeChange 屬性是SmallChange相對於使用者所看到的檢視大小設定，而非以包含未顯示部分的總大小為基準。 舉例來說，如果你有一個帶有滾動條的圖片框，顯示一張大圖片， SmallChange 且屬性 LargeChange 應該是相對於圖片框的大小設定，而不是圖片的大小。

另請參閱

• SmallChange