Richtextbox上的编号列表

Question

我正在尝试为文本编辑器添加编号列表功能。RichTextbox已经提供了SelectionBullet属性来将所选内容变成项目符号列表，但是我无法找到类似的属性来生成编号列表。是否存在标准方法在Richtextbox上创建编号列表？如果没有，我将不得不自己实现它，因此可以帮助我完成此操作的代码片段将会很有帮助。谢谢。

- yohannist

Answer 1

我知道链接通常不被视为好的答案，然而CodeProject上的文章“RichTextBox with Search Line Numbering, Bulleting, Printing, Searching Support”可能会对你寻找的内容有所帮助。

在这篇文章中，作者将RichTextBox控件扩展成可以实现你所要求的功能（以及更多），并且该代码已经发布供所有人查看。

- iMortalitySX

---

@Yohannes Yay，接受吗？我不会在这里转载别人的代码并声称是我的，这就是为什么我只提供了链接的原因。 - iMortalitySX

Answer 2

好的，我按照以下方式实施了它。

  private void btnNumbers_Click(object sender, EventArgs e)
        {
            string temptext = rtbMain.SelectedText;

            int SelectionStart = rtbMain.SelectionStart;
            int SelectionLength = rtbMain.SelectionLength;

            rtbMain.SelectionStart = rtbMain.GetFirstCharIndexOfCurrentLine();
            rtbMain.SelectionLength = 0;
            rtbMain.SelectedText = "1. ";

            int j = 2;
            for( int i = SelectionStart; i < SelectionStart + SelectionLength; i++)
                if (rtbMain.Text[i] == '\n')
                {
                    rtbMain.SelectionStart = i + 1;
                    rtbMain.SelectionLength = 0;
                    rtbMain.SelectedText = j.ToString() + ". ";
                    j++;
                    SelectionLength += 3;
                }

        }

        private void rtbMain_KeyDown(object sender, KeyEventArgs e)
        {//this piece of code automatically increments the bulleted list when user //presses Enter key
            int tempNum;
            if (e.KeyCode == Keys.Enter)
                try
                    {
                        if (char.IsDigit(rtbMain.Text[rtbMain.GetFirstCharIndexOfCurrentLine()]))
                        {
                            if (char.IsDigit(rtbMain.Text[rtbMain.GetFirstCharIndexOfCurrentLine() + 1]) && rtbMain.Text[rtbMain.GetFirstCharIndexOfCurrentLine() + 2] == '.')
                                tempNum = int.Parse(rtbMain.Text.Substring(rtbMain.GetFirstCharIndexOfCurrentLine(),2));
                            else tempNum = int.Parse(rtbMain.Text[rtbMain.GetFirstCharIndexOfCurrentLine()].ToString());

                            if (rtbMain.Text[rtbMain.GetFirstCharIndexOfCurrentLine() + 1] == '.' || (char.IsDigit(rtbMain.Text[rtbMain.GetFirstCharIndexOfCurrentLine() + 1]) && rtbMain.Text[rtbMain.GetFirstCharIndexOfCurrentLine() + 2] == '.'))
                            {
                                tempNum++;
                                    rtbMain.SelectedText = "\r\n" + tempNum.ToString() + ". ";
                                e.SuppressKeyPress = true;
                            }
                        }  
                    }
                 catch{}
        }

- yohannist

Answer 3

这是我的答案……易于阅读和改进。我采用了一种非常不同的方法，但添加了如果已经存在，则可以删除所选内容中的编号列表的功能。请注意，到目前为止，我只进行了轻微的测试，它似乎工作得不错……但可能需要进一步完善。

    private void btnOrdered_Click(object sender, EventArgs e)
    {
        string[] splitSelection = null;
        // If selection split selection else split everything
        if (this.txtCaptionEditor.SelectionLength > 0)
        {
            splitSelection = this.txtCaptionEditor.SelectedText.Replace("\r\n", "\n").Split("\n".ToCharArray());
        }
        else
        {
            splitSelection = this.txtCaptionEditor.Text.Replace("\r\n", "\n").Split("\n".ToCharArray());
        }
        bool Exists = false;
        for (int i = 0; i < splitSelection.GetLength(0); i++)
        {
            // If Ordered List Allready exists in selection then remove else add
            if (!string.IsNullOrEmpty(splitSelection[i]))
            {
                if (splitSelection[i].Substring(0, 2) == "1.") { Exists = true; }
            }
        }

        for (int i = 0; i < splitSelection.GetLength(0); i++)
        {
            int lineCount = (i + 1);
            if (Exists)
            {
                this.txtCaptionEditor.Text = this.txtCaptionEditor.Text.Replace(Convert.ToString(lineCount) + ".  ", "");
            }
            else
            {
                if(!string.IsNullOrEmpty(splitSelection[i]))
                {
                    this.txtCaptionEditor.Text = this.txtCaptionEditor.Text.Replace(splitSelection[i], Convert.ToString(lineCount) + ".  " + splitSelection[i]);
                }

            }
        }
    }

    private void txtCaptionEditor_KeyDown(object sender, KeyEventArgs e)
    {
        string[] splitSelection = this.txtCaptionEditor.Text.Replace("\r\n", "\n").Split("\n".ToCharArray());
        if (e.KeyCode == Keys.Enter)
        {
            // Get Current Line Position
            int currentLine = this.txtCaptionEditor.GetLineFromCharIndex(this.txtCaptionEditor.SelectionStart);
            // Only Run if the previous line is greater than zero
            if ((currentLine) >= 0)
            {
                // Loop through 100 possible numbers for match you can go higher 
                // If you think your numbered list could go above 100
                for (int i = 0; i < 100; i++)
                {
                    if (splitSelection[(currentLine)].Substring(0, 2) == Convert.ToString((i + 1)) + ".")
                    {
                        // If the substring of the current line equals a numbered list                value.. enumerate next line
                        this.txtCaptionEditor.SelectedText = "\n" + (i + 2) + ".  ";
                        e.SuppressKeyPress = true;
                    }
                }
            }
        }
    }

- Anthony Griggs