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TextPattern.RangeFromChild أسلوب

Visual Studio 2010

يسترد نطاق نص إحاطة عنصر فرع كصورة، رابط، Microsoft Excelجدول بيانات، أو غير ذلك تضمين الكائن.

مساحة الاسم:  System.Windows.Automation
التجميع:  UIAutomationClient (في UIAutomationClient.dll)

public TextPatternRange RangeFromChild(
	AutomationElement childElement


النوع: System.Windows.Automation.AutomationElement
The enclosed كائن.

القيمة المُرجعة

النوع: System.Windows.Automation.Text.TextPatternRange
نطاق الذي يمتد عنصر فرع.


التابع عنصر هو null.


العنصر هو غير فرع لحاوية نص.

If there هو لا موجود نص في the range الموقع the فرع عنصر موجود, a degenerate (فارغ) range هو returned.

The childElement معلمة هو either a فرع of the AutomationElement associated مع a TextPattern أو من the مصفوفه من children of a TextPatternRange.

/// -------------------------------------------------------------------
/// <summary>
/// Obtain the text control of interest from the target application.
/// </summary>
/// <param name="targetApp">
/// The target application.
/// </param>
/// <returns>
/// An AutomationElement that represents a text provider..
/// </returns>
/// -------------------------------------------------------------------
private AutomationElement GetTextElement(AutomationElement targetApp)
    // The control type we're looking for; in this case 'Document'
    PropertyCondition cond1 =
        new PropertyCondition(

    // The control pattern of interest; in this case 'TextPattern'.
    PropertyCondition cond2 = 
        new PropertyCondition(

    AndCondition textCondition = new AndCondition(cond1, cond2);

    AutomationElement targetTextElement =
        targetApp.FindFirst(TreeScope.Descendants, textCondition);

    // If targetText is null then a suitable text control was not found.
    return targetTextElement;


/// -------------------------------------------------------------------
/// <summary>
/// Obtains a text range spanning an embedded child 
/// of a document control and displays the content of the range.
/// </summary>
/// <param name="targetTextElement">
/// The AutomationElment that represents a text control.
/// </param>
/// -------------------------------------------------------------------
private void GetRangeFromChild(AutomationElement targetTextElement)
    TextPattern textPattern =
        as TextPattern;

    if (textPattern == null)
        // Target control doesn't support TextPattern.

    // Obtain a text range spanning the entire document.
    TextPatternRange textRange = textPattern.DocumentRange;

    // Retrieve the embedded objects within the range.
    AutomationElement[] embeddedObjects = textRange.GetChildren();

    // Retrieve and display text value of embedded object.
    foreach (AutomationElement embeddedObject in embeddedObjects)
        if ((bool)embeddedObject.GetCurrentPropertyValue(
           // For full functionality a secondary TextPattern should
           // be obtained from the embedded object.
           // embeddedObject must be a child of the text provider.
            TextPatternRange embeddedObjectRange =
            // GetText(-1) retrieves all text in the range.
            // Typically a more limited amount of text would be 
            // retrieved for performance and security reasons.

نظام التشغيل Windows 7, Windows Vista, Windows XP SP2, Windows Server 2008, نظام التشغيل Windows Server 2003

لا يدعم .NET Framework و .NET Compact Framework كافة الإصدارات الخاصة بكل نظام أساسي. للحصول على قائمة بالإصدارات المدعمة، راجع متطلبات النظام إطار عمل .NET.

.NET Framework

مدعوم في: 4, 3.5, 3.0

NET Framework. Client Profile

مدعوم في: 4