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TextPointer.GetNextInsertionPosition(LogicalDirection) Method

  • Reference

Definition

Namespace:
System.Windows.Documents
Assembly:
PresentationFramework.dll

Returns a TextPointer to the next insertion position in the specified logical direction.

public:
 System::Windows::Documents::TextPointer ^ GetNextInsertionPosition(System::Windows::Documents::LogicalDirection direction);
public System.Windows.Documents.TextPointer GetNextInsertionPosition (System.Windows.Documents.LogicalDirection direction);
member this.GetNextInsertionPosition : System.Windows.Documents.LogicalDirection -> System.Windows.Documents.TextPointer
Public Function GetNextInsertionPosition (direction As LogicalDirection) As TextPointer

Parameters

direction
LogicalDirection

One of the LogicalDirection values that specifies the logical direction in which to search for the next insertion position.

Returns

TextPointer

A TextPointer that identifies the next insertion position in the requested direction, or null if no next insertion position can be found.

Examples

The following example demonstrates a use for this method. The example uses the GetNextInsertionPosition method to traverse content element boundaries in order to count the number of Paragraph elements present between two specified TextPointer instances.

// This method returns the number of pagragraphs between two
// specified TextPointers.
int GetParagraphCount(TextPointer start, TextPointer end)
{
    int paragraphCount = 0;
 
    while (start != null && start.CompareTo(end) < 0)
    {
        Paragraph paragraph = start.Paragraph;
 
        if (paragraph != null)
        {
            paragraphCount++;
 
            // Advance start to the end of the current paragraph.
            start = paragraph.ContentEnd;
         }
 
         // Use the GetNextInsertionPosition method to skip over any interceding
         // content element tags.
         start = start.GetNextInsertionPosition(LogicalDirection.Forward);
     } // End while.
 
         return paragraphCount;
}  // End GetParagraphCount.

' This method returns the number of pagragraphs between two
' specified TextPointers.
Private Function GetParagraphCount(ByVal start As TextPointer, ByVal [end] As TextPointer) As Integer
    Dim paragraphCount As Integer = 0

    Do While start IsNot Nothing AndAlso start.CompareTo([end]) < 0
        Dim paragraph As Paragraph = start.Paragraph

        If paragraph IsNot Nothing Then
            paragraphCount += 1

            ' Advance start to the end of the current paragraph.
            start = paragraph.ContentEnd
        End If

        ' Use the GetNextInsertionPosition method to skip over any interceding
        ' content element tags.
        start = start.GetNextInsertionPosition(LogicalDirection.Forward)

    Loop ' End while.

    Return paragraphCount

End Function ' End GetParagraphCount.

Remarks

An insertion position is a position where new content may be added without breaking any semantic rules for the associated content. In practice, an insertion position is anywhere in content where a caret may be positioned. An example of a valid TextPointer position that is not an insertion position is the position between two adjacent Paragraph tags (that is, between the closing tag of the preceding paragraph and the opening tag of the next paragraph).

Applies to

See also