c# - WPF 中 RichTextBox 内的光标位置

Question

我正在开发一个小型 WPF 应用程序，其中有多个选项卡。我在底部有一个状态栏；要求是显示光标的行号和列。因此，当用户更改光标位置时，行号和列必须自动更新。这是我添加 RichTextBox 的代码；计算行号和列的代码在 KeyDown 事件处理程序中，但永远不会调用此事件。我应该处理哪个事件来获取光标的行号和列？

private void AddTabitem(string filePath, mode fileMode)
{
    if (fileMode == mode.openFile)
    {
        if (File.Exists(filePath))
        {
            RichTextBox mcRTB = new RichTextBox();
            mcRTB.KeyDown += new KeyEventHandler(LineNumber);
//rest of the code goes here
        }
    }
}
mcRTB.KeyDown += new KeyEventHandler(LineNumber);

private void LineNumber(object sender, KeyEventArgs e)
{          
    TextPointer tp1 = rtbList[EditorTabcontrol.SelectedIndex].Selection.Start.GetLineStartPosition(0);
    TextPointer tp2 = rtbList[EditorTabcontrol.SelectedIndex].Selection.Start;

    int column = tp1.GetOffsetToPosition(tp2);

    int someBigNumber = int.MaxValue;
    int lineMoved, currentLineNumber;
    rtbList[EditorTabcontrol.SelectedIndex].Selection.Start.GetLineStartPosition(-someBigNumber, out lineMoved);
    currentLineNumber = -lineMoved;
    string LineColumnLabel;

    //LineColumnLabel.Content = "Line: " + currentLineNumber.ToString() + " Column: " + column.ToString();
    LineColumnLabel = "Line: " + currentLineNumber.ToString() + " Column: " + column.ToString();        
}

Answer 1

在 MSDN ( http://msdn.microsoft.com/en-us/library/system.windows.controls.richtextbox.caretposition%28v=vs.110%29.aspx ) 上有一个针对您的任务的标准示例。请注意，在此上下文中，“光标”称为“插入符号”。来自 MSDN 的示例如下:

// 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;