語言

ScrollPattern.SetScrollPercent(Double, Double) 方法

定義

命名空間:
System.Windows.Automation
組件:
UIAutomationClient.dll

將水平及/或垂直捲動位置設定為該區域內 AutomationElement總內容區域的百分比。

public:
 void SetScrollPercent(double horizontalPercent, double verticalPercent);
public void SetScrollPercent(double horizontalPercent, double verticalPercent);
member this.SetScrollPercent : double * double -> unit
Public Sub SetScrollPercent (horizontalPercent As Double, verticalPercent As Double)

參數

horizontalPercent
Double

佔總水平內容面積的百分比。 NoScroll 如果無法將控制項往此方向滾動，應該會傳入。

verticalPercent
Double

佔整個垂直內容區域的百分比。 NoScroll 如果無法將控制項往此方向滾動，應該會傳入。

例外狀況

ArgumentException

無法轉換成雙重的值會被傳遞進去。

ArgumentOutOfRangeException

大於 100 或小於 0 的值會被傳送（除 -1 外，該值等同 NoScroll於 ）。 HorizontalScrollPercent與VerticalScrollPercent值會被正規化為0% 或100%。

InvalidOperationException

嘗試向無支撐方向捲動。

範例

在以下範例中， ScrollPattern 從 取得 AutomationElement 一個控制模式，然後用來將可查看區域捲動到內容區的左上角「主頁」位置。

///--------------------------------------------------------------------
/// <summary>
/// Obtains a ScrollPattern control pattern from an 
/// automation element.
/// </summary>
/// <param name="targetControl">
/// The automation element of interest.
/// </param>
/// <returns>
/// A ScrollPattern object.
/// </returns>
///--------------------------------------------------------------------
private ScrollPattern GetScrollPattern(
    AutomationElement targetControl)
{
    ScrollPattern scrollPattern = null;

    try
    {
        scrollPattern =
            targetControl.GetCurrentPattern(
            ScrollPattern.Pattern)
            as ScrollPattern;
    }
    // Object doesn't support the ScrollPattern control pattern
    catch (InvalidOperationException)
    {
        return null;
    }

    return scrollPattern;
}

'''--------------------------------------------------------------------
''' <summary>
''' Obtains a ScrollPattern control pattern from an 
''' automation element.
''' </summary>
''' <param name="targetControl">
''' The automation element of interest.
''' </param>
''' <returns>
''' A ScrollPattern object.
''' </returns>
'''--------------------------------------------------------------------
Private Function GetScrollPattern( _
ByVal targetControl As AutomationElement) As ScrollPattern
    Dim scrollPattern As ScrollPattern = Nothing

    Try
        scrollPattern = DirectCast( _
        targetControl.GetCurrentPattern(scrollPattern.Pattern), _
        ScrollPattern)
    Catch
        ' Object doesn't support the ScrollPattern control pattern
        Return Nothing
    End Try

    Return scrollPattern

End Function 'GetScrollPattern

///--------------------------------------------------------------------
/// <summary>
/// Obtains a ScrollPattern control pattern from an automation 
/// element and attempts to scroll to the 'home' position.
/// </summary>
/// <param name="targetControl">
/// The automation element of interest.
/// </param>
///--------------------------------------------------------------------
private void ScrollHome(AutomationElement targetControl)
{
    if (targetControl == null)
    {
        throw new ArgumentNullException(
            "AutomationElement argument cannot be null.");
    }

    ScrollPattern scrollPattern = GetScrollPattern(targetControl);

    if (scrollPattern == null)
    {
        return;
    }

    try
    {
        scrollPattern.SetScrollPercent(0, 0);
    }
    catch (InvalidOperationException)
    {
        // Control not able to scroll in the direction requested;
        // when scrollable property of that direction is False
        // TO DO: error handling.
    }
    catch (ArgumentOutOfRangeException)
    {
        // A value greater than 100 or less than 0 is passed in 
        // (except -1 which is equivalent to NoScroll).
        // TO DO: error handling.
    }
}

'''--------------------------------------------------------------------
''' <summary>
''' Obtains a ScrollPattern control pattern from an automation 
''' element and attempts to scroll to the top left 'home' position.
''' </summary>
''' <param name="targetControl">
''' The automation element of interest.
''' </param>
'''--------------------------------------------------------------------
Private Sub ScrollHome(ByVal targetControl As AutomationElement) 
    If targetControl Is Nothing Then
        Throw New ArgumentNullException( _
        "AutomationElement argument cannot be null.")
    End If
    
    Dim scrollPattern As ScrollPattern = _
    GetScrollPattern(targetControl)
    
    If scrollPattern Is Nothing Then
        Return
    End If
    
    Try
        scrollPattern.SetScrollPercent(0, 0)
    Catch exc As InvalidOperationException
        ' Control not able to scroll in the direction requested;
        ' when scrollable property of that direction is False
        ' TO DO: error handling.
    Catch exc As ArgumentOutOfRangeException
        ' A value greater than 100 or less than 0 is passed in 
        ' (except -1 which is equivalent to NoScroll).
        ' TO DO: error handling.
    End Try

End Sub

備註

此方法僅在控制區內容區大於可見區時有效。

輸入該值 NoScroll 表示指定方向沒有滾動。

適用於