Menemukan Elemen Automasi Antarmuka Pengguna untuk Item Daftar

Catatan

Dokumentasi ini ditujukan untuk pengembang .NET Framework yang ingin menggunakan kelas UI Automation terkelola yang ditentukan pada namespace System.Windows.Automation. Untuk informasi terbaru tentang UI Automation, lihat API Automasi Windows: Automasi Antarmuka Pengguna.

Topik ini menunjukkan cara mengambil AutomationElement untuk item dalam daftar saat indeks item diketahui.

Contoh

Contoh berikut menunjukkan dua cara mengambil item tertentu dari daftar, satu menggunakan TreeWalker dan yang lainnya menggunakan FindAll.

Teknik pertama cenderung lebih cepat untuk kontrol Win32, tetapi yang kedua lebih cepat untuk kontrol Windows Presentation Foundation (WPF).

/// <summary>
/// Retrieves an element in a list, using TreeWalker.
/// </summary>
/// <param name="parent">The list element.</param>
/// <param name="index">The index of the element to find.</param>
/// <returns>The list item.</returns>
AutomationElement FindChildAt(AutomationElement parent, int index)
{
    if (index < 0)
    {
        throw new ArgumentOutOfRangeException();
    }
    TreeWalker walker = TreeWalker.ControlViewWalker;
    AutomationElement child = walker.GetFirstChild(parent);
    for (int x = 1; x <= index; x++)
    {
        child = walker.GetNextSibling(child);
        if (child == null)
        {
            throw new ArgumentOutOfRangeException();
        }
    }
    return child;
}

/// <summary>
/// Retrieves an element in a list, using FindAll.
/// </summary>
/// <param name="parent">The list element.</param>
/// <param name="index">The index of the element to find.</param>
/// <returns>The list item.</returns>
AutomationElement FindChildAtB(AutomationElement parent, int index)
{
    Condition findCondition = new PropertyCondition(AutomationElement.IsControlElementProperty, true);
    AutomationElementCollection found = parent.FindAll(TreeScope.Children, findCondition);
    if ((index < 0) || (index >= found.Count))
    {
        throw new ArgumentOutOfRangeException();
    }
    return found[index];
}

''' <summary>
''' Retrieves an element in a list, using TreeWalker.
''' </summary>
''' <param name="parent">The list element.</param>
''' <param name="index">The index of the element to find.</param>
''' <returns>The list item.</returns>
Function FindChildAt(ByVal parent As AutomationElement, ByVal index As Integer) As AutomationElement

    If (index < 0) Then
        Throw New ArgumentOutOfRangeException()
    End If
    Dim walker As TreeWalker = TreeWalker.ControlViewWalker
    Dim child As AutomationElement = walker.GetFirstChild(parent)
    For x As Integer = 1 To (index - 1)
        child = walker.GetNextSibling(child)
        If child = Nothing Then

            Throw New ArgumentOutOfRangeException()
        End If
    Next x
    Return child
End Function

''' <summary>
''' Retrieves an element in a list, using FindAll.
''' </summary>
''' <param name="parent">The list element.</param>
''' <param name="index">The index of the element to find.</param>
''' <returns>The list item.</returns>
Function FindChildAtB(ByVal parent As AutomationElement, ByVal index As Integer) As AutomationElement
    Dim findCondition As Condition = _
        New PropertyCondition(AutomationElement.IsControlElementProperty, True)
    Dim found As AutomationElementCollection = parent.FindAll(TreeScope.Children, findCondition)
    If (index < 0) Or (index >= found.Count) Then
        Throw New ArgumentOutOfRangeException()
    End If
    Return found(index)
End Function

Lihat juga

• Mendapatkan Elemen UI Automation