在RichTextBox中設置插入/光標位置 - WPF

Question

如何在WPF中的RichTextBox中設置插入符/光標位置？

我使用MSDN CaretPosition中的代碼，但似乎無法設置光標？

// Create a new FlowDocument, and add 3 paragraphs.
FlowDocument flowDoc = new FlowDocument();
flowDoc.Blocks.Add(new Paragraph(new Run("Paragraph 1"))); 
flowDoc.Blocks.Add(new Paragraph(new Run("Paragraph 2"))); 
flowDoc.Blocks.Add(new Paragraph(new Run("Paragraph 3")));
// Set the FlowDocument to be the content for a new RichTextBox.
RichTextBox rtb = new RichTextBox(flowDoc);

// Get the current caret position.
TextPointer caretPos = rtb.CaretPosition;

// Set the TextPointer to the end of the current document.
caretPos = caretPos.DocumentEnd;

// Specify the new caret position at the end of the current document.
rtb.CaretPosition = caretPos;

Answer 1

如何在WPF中的RichTextBox中設置插入符/光標位置？

假設rtb是RichTextBox的名稱，具有不同的塊和內聯 ，您可以通過以下方式在文檔的開頭設置Caret：

rtb.CaretPosition = rtb.CaretPosition.DocumentStart;

或者在結尾處：

rtb.CaretPosition = rtb.CaretPosition.DocumentEnd;

另一方面，假設您有一個特定的段落或塊，例如：

Block blk = rtb.Document.Blocks.ElementAt(1);

您可以將插入符號設置為它的開頭

rtb.CaretPosition = blk.ContentStart;

或它的結束

rtb.CaretPosition = blk.ContentEnd;

或者如果您有特定的內聯，例如

Run r = ((Paragraph)rtb.Document.Blocks.ElementAt(0)).Inlines.ElementAt(1) as Run;

你也可以使用

rtb.CaretPosition = r.ContentStart;
rtb.CaretPosition = r.ContentEnd;

當然，如果您使用從右到左和從左到右文本的復雜段落，您可能需要考慮

rtb.CaretPosition = blk.ElementStart;
rtb.CaretPosition = blk.ElementEnd;

還要注意TextPointer實現的不同方法，您可以使用它們來訪問文檔/塊/內聯的不同部分：

rtb.CaretPosition = rtb.CaretPosition.GetLineStartPosition(0);
rtb.CaretPosition = rtb.CaretPosition.GetPositionAtOffset(2);

有關更多方法和更多信息，請參閱鏈接。

最后，您可能希望使用塊或內聯中實現的BringIntoView方法：

blk.BringIntoView();
r.BringIntoView();

並設置鍵盤焦點，以查看Caret的閃爍：

Keyboard.Focus(rtb);

Answer 2

請記住設置焦點，以便光標出現在RichTextBox中：

// Create a new FlowDocument, and add 3 paragraphs.
FlowDocument flowDoc = new FlowDocument();
flowDoc.Blocks.Add(new Paragraph(new Run("Paragraph 1"))); 
flowDoc.Blocks.Add(new Paragraph(new Run("Paragraph 2"))); 
flowDoc.Blocks.Add(new Paragraph(new Run("Paragraph 3")));
// Set the FlowDocument to be the content for a new RichTextBox.
RichTextBox rtb = new RichTextBox(flowDoc);

//****SET FOCUS****
rtb.Focus();

// Get the current caret position.
TextPointer caretPos = rtb.CaretPosition;
// Set the TextPointer to the end of the current document.
caretPos = caretPos.DocumentEnd;
// Specify the new caret position at the end of the current document.
rtb.CaretPosition = caretPos;

。

除了設置到文件結尾，您可以使用GetPositionAtOffset設置caretPos backward / forward要移動和位移量：

int displacement = 8;

// Set the TextPointer 8 displacement backward.
caretPos = caretPos.GetPositionAtOffset(displacement, LogicalDirection.Backward);

。

例如，您可以將其粘貼到空窗口的構造函數中以進行測試：

    public RichTbxFlowDocumentTest()
    {
        InitializeComponent();

        // Create a new FlowDocument, and add 3 paragraphs.
        FlowDocument flowDoc = new FlowDocument();
        flowDoc.Blocks.Add(new Paragraph(new Run("Paragraph 1")));
        flowDoc.Blocks.Add(new Paragraph(new Run("Paragraph 2")));
        flowDoc.Blocks.Add(new Paragraph(new Run("Paragraph 3")));
        // Set the FlowDocument to be the content for a new RichTextBox.
        RichTextBox rtb = new RichTextBox(flowDoc);

        //Add RichTextBox and Button with setting cursor method to a new StackPanel
        StackPanel s = new StackPanel();
        Button button = new Button() { Content = "Set Cursor Pos" };
        button.Click += (sender, e) =>
        {
            //SET FOCUS
            rtb.Focus();

            // Get the current caret position.
            TextPointer caretPos = rtb.CaretPosition;

            //Set amount of displacement
            int displacement = 6;

            // Set the TextPointer 6 displacement backward
            caretPos = caretPos.GetPositionAtOffset(displacement, LogicalDirection.Backward);

            // Specify the new caret position to RichTextBox
            rtb.CaretPosition = caretPos;
        };
        s.Children.Add(button);
        s.Children.Add(rtb);
        this.Content = s;
    }
}

。

結果：

（我在中間移動窗口以防止殘像）

。

其他補充：

如果要將RichTextBox插入符向上或向下移動一行，可以查看https://social.msdn.microsoft.com/Forums/vstudio/en-US/8c34e7b1-91ed-4b11-979d-d18b28a71f6f/how-do-你-移動- RichTextBox中，脫字上調或者下調單行？論壇= WPF

myRichTextBox.Focus();
EditingCommands.MoveUpByLine.Execute(null, myRichTextBox);