Hinzufügen von Inhalt in einem Textfeld mithilfe von Benutzeroberflächenautomatisierung
Hinweis
Diese Dokumentation ist für .NET Framework-Entwickler konzipiert, die die verwalteten Klassen zur Automatisierung der Benutzeroberfläche verwenden möchten, die im Namespace System.Windows.Automation definiert sind. Aktuelle Informationen zur Automatisierung der Benutzeroberfläche finden Sie auf der Seite zur Windows-Automatisierungs-API: Benutzeroberflächenautomatisierung.
Dieses Thema enthält Beispielcode, der veranschaulicht, wie die Microsoft-Benutzeroberflächenautomatisierung zum Einfügen von Text in ein einzeiliges Textfeld verwendet werden kann. Für mehrzeilige Steuerelemente und Rich-Text-Steuerelemente, bei denen die Benutzeroberflächenautomatisierung nicht anwendbar ist, steht eine alternative Methode zur Verfügung. Zu Vergleichszwecken zeigt das Beispiel außerdem, wie Sie mit Win32-Methoden die gleichen Ergebnisse erzielen können.
Beispiel
Das folgende Beispiel führt Sie durch eine Sequenz von Textsteuerelementen in einer Zielanwendung. Jedes Textsteuerelement wird getestet, um zu überprüfen, ob daraus mithilfe der TryGetCurrentPattern-Methode ein ValuePattern-Objekt abgerufen werden kann. Wenn das Textsteuerelement ValuePattern unterstützt, wird mithilfe der Methode SetValue eine benutzerdefinierte Zeichenfolge in das Textsteuerelement eingefügt. Andernfalls wird die Methode SendKeys.SendWait verwendet.
///--------------------------------------------------------------------
/// <summary>
/// Sets the values of the text controls using managed methods.
/// </summary>
/// <param name="s">The string to be inserted.</param>
///--------------------------------------------------------------------
private void SetValueWithUIAutomation(string s)
{
foreach (AutomationElement control in textControls)
{
InsertTextUsingUIAutomation(control, s);
}
}
///--------------------------------------------------------------------
/// <summary>
/// Inserts a string into each text control of interest.
/// </summary>
/// <param name="element">A text control.</param>
/// <param name="value">The string to be inserted.</param>
///--------------------------------------------------------------------
private void InsertTextUsingUIAutomation(AutomationElement element,
string value)
{
try
{
// Validate arguments / initial setup
if (value == null)
throw new ArgumentNullException(
"String parameter must not be null.");
if (element == null)
throw new ArgumentNullException(
"AutomationElement parameter must not be null");
// A series of basic checks prior to attempting an insertion.
//
// Check #1: Is control enabled?
// An alternative to testing for static or read-only controls
// is to filter using
// PropertyCondition(AutomationElement.IsEnabledProperty, true)
// and exclude all read-only text controls from the collection.
if (!element.Current.IsEnabled)
{
throw new InvalidOperationException(
"The control with an AutomationID of "
+ element.Current.AutomationId.ToString()
+ " is not enabled.\n\n");
}
// Check #2: Are there styles that prohibit us
// from sending text to this control?
if (!element.Current.IsKeyboardFocusable)
{
throw new InvalidOperationException(
"The control with an AutomationID of "
+ element.Current.AutomationId.ToString()
+ "is read-only.\n\n");
}
// Once you have an instance of an AutomationElement,
// check if it supports the ValuePattern pattern.
object valuePattern = null;
// Control does not support the ValuePattern pattern
// so use keyboard input to insert content.
//
// NOTE: Elements that support TextPattern
// do not support ValuePattern and TextPattern
// does not support setting the text of
// multi-line edit or document controls.
// For this reason, text input must be simulated
// using one of the following methods.
//
if (!element.TryGetCurrentPattern(
ValuePattern.Pattern, out valuePattern))
{
feedbackText.Append("The control with an AutomationID of ")
.Append(element.Current.AutomationId.ToString())
.Append(" does not support ValuePattern.")
.AppendLine(" Using keyboard input.\n");
// Set focus for input functionality and begin.
element.SetFocus();
// Pause before sending keyboard input.
Thread.Sleep(100);
// Delete existing content in the control and insert new content.
SendKeys.SendWait("^{HOME}"); // Move to start of control
SendKeys.SendWait("^+{END}"); // Select everything
SendKeys.SendWait("{DEL}"); // Delete selection
SendKeys.SendWait(value);
}
// Control supports the ValuePattern pattern so we can
// use the SetValue method to insert content.
else
{
feedbackText.Append("The control with an AutomationID of ")
.Append(element.Current.AutomationId.ToString())
.Append((" supports ValuePattern."))
.AppendLine(" Using ValuePattern.SetValue().\n");
// Set focus for input functionality and begin.
element.SetFocus();
((ValuePattern)valuePattern).SetValue(value);
}
}
catch (ArgumentNullException exc)
{
feedbackText.Append(exc.Message);
}
catch (InvalidOperationException exc)
{
feedbackText.Append(exc.Message);
}
finally
{
Feedback(feedbackText.ToString());
}
}
'' --------------------------------------------------------------------
'' <summary>
'' Sets the values of the text controls using managed methods.
'' </summary>
'' <param name="s">The string to be inserted.</param>
'' --------------------------------------------------------------------
Private Sub SetValueWithUIAutomation(ByVal s As String)
Dim control As AutomationElement
For Each control In textControls
InsertTextWithUIAutomation(control, s)
Next control
End Sub
'' --------------------------------------------------------------------
'' <summary>
'' Inserts a string into each text control of interest.
'' </summary>
'' <param name="element">A text control.</param>
'' <param name="value">The string to be inserted.</param>
'' --------------------------------------------------------------------
Private Sub InsertTextWithUIAutomation( _
ByVal element As AutomationElement, ByVal value As String)
Try
' Validate arguments / initial setup
If value Is Nothing Then
Throw New ArgumentNullException( _
"String parameter must not be null.")
End If
If element Is Nothing Then
Throw New ArgumentNullException( _
"AutomationElement parameter must not be null")
End If
' A series of basic checks prior to attempting an insertion.
'
' Check #1: Is control enabled?
' An alternative to testing for static or read-only controls
' is to filter using
' PropertyCondition(AutomationElement.IsEnabledProperty, true)
' and exclude all read-only text controls from the collection.
If Not element.Current.IsEnabled Then
Throw New InvalidOperationException( _
"The control with an AutomationID of " + _
element.Current.AutomationId.ToString() + _
" is not enabled." + vbLf + vbLf)
End If
' Check #2: Are there styles that prohibit us
' from sending text to this control?
If Not element.Current.IsKeyboardFocusable Then
Throw New InvalidOperationException( _
"The control with an AutomationID of " + _
element.Current.AutomationId.ToString() + _
"is read-only." + vbLf + vbLf)
End If
' Once you have an instance of an AutomationElement,
' check if it supports the ValuePattern pattern.
Dim targetValuePattern As Object = Nothing
' Control does not support the ValuePattern pattern
' so use keyboard input to insert content.
'
' NOTE: Elements that support TextPattern
' do not support ValuePattern and TextPattern
' does not support setting the text of
' multi-line edit or document controls.
' For this reason, text input must be simulated
' using one of the following methods.
'
If Not element.TryGetCurrentPattern(ValuePattern.Pattern, targetValuePattern) Then
feedbackText.Append("The control with an AutomationID of ") _
.Append(element.Current.AutomationId.ToString()) _
.Append(" does not support ValuePattern."). _
AppendLine(" Using keyboard input.").AppendLine()
' Set focus for input functionality and begin.
element.SetFocus()
' Pause before sending keyboard input.
Thread.Sleep(100)
' Delete existing content in the control and insert new content.
SendKeys.SendWait("^{HOME}") ' Move to start of control
SendKeys.SendWait("^+{END}") ' Select everything
SendKeys.SendWait("{DEL}") ' Delete selection
SendKeys.SendWait(value)
Else
' Control supports the ValuePattern pattern so we can
' use the SetValue method to insert content.
feedbackText.Append("The control with an AutomationID of ") _
.Append(element.Current.AutomationId.ToString()) _
.Append(" supports ValuePattern.") _
.AppendLine(" Using ValuePattern.SetValue().").AppendLine()
' Set focus for input functionality and begin.
element.SetFocus()
Dim valueControlPattern As ValuePattern = _
DirectCast(targetValuePattern, ValuePattern)
valueControlPattern.SetValue(value)
End If
Catch exc As ArgumentNullException
feedbackText.Append(exc.Message)
Catch exc As InvalidOperationException
feedbackText.Append(exc.Message)
Finally
Feedback(feedbackText.ToString())
End Try
End Sub