Udostępnij za pośrednictwem


ScrollPattern.ScrollHorizontal(ScrollAmount) Metoda

Definicja

Przewija aktualnie widoczny region obszaru zawartości w poziomie, określony ScrollAmountelement .

public:
 void ScrollHorizontal(System::Windows::Automation::ScrollAmount amount);
public void ScrollHorizontal (System.Windows.Automation.ScrollAmount amount);
member this.ScrollHorizontal : System.Windows.Automation.ScrollAmount -> unit
Public Sub ScrollHorizontal (amount As ScrollAmount)

Parametry

amount
ScrollAmount

Pozioma ScrollAmount inkrementacja specyficzna dla kontrolki.

Wyjątki

Jeśli kontrolka obsługuje SmallIncrement wyłącznie wartości dla przewijania poziomego lub pionowego, ale LargeIncrement wartość jest przekazywana.

Podjęto próbę przewinięcia w nieobsługiwanym kierunku.

Przykłady

W poniższym przykładzie ScrollPattern wzorzec kontrolki jest uzyskiwany z elementu AutomationElement , a następnie służy do poziomego przewijania elementu żądanej kwoty.

///--------------------------------------------------------------------
/// <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 horizontally scroll the requested amount.
/// </summary>
/// <param name="targetControl">
/// The automation element of interest.
/// </param>
/// <param name="hScrollAmount">
/// The requested horizontal scroll amount.
/// </param>
///--------------------------------------------------------------------
private void ScrollElementHorizontally(
    AutomationElement targetControl,
    ScrollAmount hScrollAmount)
{
    if (targetControl == null)
    {
        throw new ArgumentNullException(
            "AutomationElement argument cannot be null.");
    }

    ScrollPattern scrollPattern = GetScrollPattern(targetControl);

    if (scrollPattern == null)
    {
        return;
    }

    if (!scrollPattern.Current.HorizontallyScrollable)
    {
        return;
    }

    try
    {
        scrollPattern.ScrollHorizontal(hScrollAmount);
    }
    catch (InvalidOperationException)
    {
        // Control not able to scroll in the direction requested;
        // when scrollable property of that direction is False
        // TO DO: error handling.
    }
    catch (ArgumentException)
    {
        // If a control supports SmallIncrement values exclusively 
        // for horizontal or vertical scrolling but a LargeIncrement 
        // value (NaN if not supported) is passed in.
        // TO DO: error handling.
    }
}
'''--------------------------------------------------------------------
''' <summary>
''' Obtains a ScrollPattern control pattern from an automation 
''' element and attempts to horizontally scroll the requested amount.
''' </summary>
''' <param name="targetControl">
''' The automation element of interest.
''' </param>
''' <param name="hScrollAmount">
''' The requested horizontal scroll amount.
''' </param>
'''--------------------------------------------------------------------
Private Sub ScrollElementHorizontally( _
ByVal targetControl As AutomationElement, _
ByVal hScrollAmount As ScrollAmount)
    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

    If Not scrollPattern.Current.HorizontallyScrollable Then
        Return
    End If

    Try
        scrollPattern.ScrollHorizontal(hScrollAmount)
    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 ArgumentException
        ' If a control supports SmallIncrement values exclusively 
        ' for horizontal or vertical scrolling but a LargeIncrement 
        ' value (NaN if not supported) is passed in.
        ' TO DO: error handling.
    End Try

End Sub

Dotyczy

Zobacz też