ValuePattern.ValuePatternInformation.IsReadOnly Propriété

Définition

Obtient une valeur qui spécifie si la valeur d’un élément UI Automation est en lecture seule.

public:
 property bool IsReadOnly { bool get(); };
public bool IsReadOnly { get; }
member this.IsReadOnly : bool
Public ReadOnly Property IsReadOnly As Boolean

Valeur de propriété

true si la valeur est en lecture seule ; false si elle peut être modifiée.

Exemples

Dans l’exemple suivant, un AutomationElement qui prend en charge le ValuePattern modèle de contrôle est ValueProperty défini sur une valeur spécifiée par l’utilisateur.

///--------------------------------------------------------------------
/// <summary>
/// Inserts a string into a text control that supports ValuePattern.
/// </summary>
/// <param name="targetControl">A text control.</param>
/// <param name="value">The string to be inserted.</param>
///--------------------------------------------------------------------
private void InsertText(AutomationElement targetControl,
                                    string value)
{
    // Validate arguments / initial setup
    if (value == null)
        throw new ArgumentNullException(
            "String parameter must not be null.");

    if (targetControl == 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 (!targetControl.Current.IsEnabled)
    {
        throw new InvalidOperationException(
            "The control is not enabled.\n\n");
    }

    // Check #2: Are there styles that prohibit us 
    //           from sending text to this control?
    if (!targetControl.Current.IsKeyboardFocusable)
    {
        throw new InvalidOperationException(
            "The control is not focusable.\n\n");
    }

    // Once you have an instance of an AutomationElement,  
    // check if it supports the ValuePattern pattern.
    object valuePattern = null;

    if (!targetControl.TryGetCurrentPattern(
        ValuePattern.Pattern, out valuePattern))
    {
        // 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.
    }
    // Control supports the ValuePattern pattern so we can 
    // use the SetValue method to insert content.
    else
    {
        if (((ValuePattern)valuePattern).Current.IsReadOnly)
        {
            throw new InvalidOperationException(
                "The control is read-only.");
        }
        else
        {
            ((ValuePattern)valuePattern).SetValue(value);
        }
    }
}
'''--------------------------------------------------------------------
''' <summary>
''' Inserts a string into a text control that supports ValuePattern.
''' </summary>
''' <param name="targetControl">A text control.</param>
''' <param name="value">The string to be inserted.</param>
'''--------------------------------------------------------------------
Private Sub InsertText(ByVal targetControl As AutomationElement, _
ByVal value As String)
    ' Validate arguments / initial setup
    If value Is Nothing Then
        Throw New ArgumentNullException( _
        "String parameter must not be null.")
    End If

    If targetControl 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 targetControl.Current.IsEnabled Then
        Throw New InvalidOperationException( _
        "The control is not enabled." + vbLf + vbLf)
    End If

    ' Check #2: Are there styles that prohibit us 
    '           from sending text to this control?
    If Not targetControl.Current.IsKeyboardFocusable Then
        Throw New InvalidOperationException( _
        "The control is not focusable." + vbLf + vbLf)
    End If

    ' Once you have an instance of an AutomationElement,  
    ' check if it supports the ValuePattern pattern.
    Dim valuePattern As Object = Nothing

    If Not targetControl.TryGetCurrentPattern( _
    valuePattern.Pattern, valuePattern) Then
        ' 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.
        ' Control supports the ValuePattern pattern so we can 
        ' use the SetValue method to insert content.
    Else
        If CType(valuePattern, ValuePattern).Current.IsReadOnly Then
            Throw New InvalidOperationException("The control is read-only.")
        Else
            CType(valuePattern, ValuePattern).SetValue(value)
        End If
    End If

End Sub

Remarques

Un contrôle doit avoir la IsEnabledProperty valeur true et IsReadOnlyProperty la valeur définie false sur avant que le client ne tente d’appeler SetValue.

S’applique à

Voir aussi