C# RichTextBox.Select方法代码示例

        /// <summary>
        /// Highlight all words that matches.
        /// </summary>
        /// <param name="myRtb">Source text box</param>
        /// <param name="word">Word to match.</param>
        public void HighlightText(RichTextBox myRtb, string word)
        {
            myRtb.SelectAll();
            myRtb.SelectionBackColor = Color.White;
            myRtb.SelectionColor = Color.Black;
            myRtb.DeselectAll();

            if (word == "")
            {
                return;
            }

            int s_start = myRtb.SelectionStart, startIndex = 0, index;

            while ((index = myRtb.Text.IndexOf(word, startIndex)) != -1)
            {
                myRtb.Select(index, word.Length);
                myRtb.SelectionColor = Color.White;
                myRtb.SelectionBackColor = Color.Green;

                startIndex = index + word.Length;
            }

            myRtb.SelectionStart = s_start;
            myRtb.SelectionLength = 0;
            myRtb.SelectionColor = Color.Black;
            myRtb.SelectionBackColor = Color.White;
        }

 private void setFontStyle(RichTextBox rtb, FontStyle style)
 {
     if (rtb.SelectionLength == 0)
         setCharFontStyle(rtb, style);
     else
     {
         // to avoid screen refreshing, we create a fake RichTextBox
         using (RichTextBox a = new RichTextBox())
         {
             a.SuspendLayout();
             a.SelectedRtf = rtb.SelectedRtf;
             a.SelectAll();
             int selectionStart = a.SelectionStart;
             int selectionLength = a.SelectionLength;
             int selectionEnd = selectionStart + selectionLength;
             for (int x = selectionStart; x < selectionEnd; ++x)
             {
                 // Set temporary selection
                 a.Select(x, 1);
                 // Toggle font style of the selection
                 setCharFontStyle(a, style);
             }
             // Restore the original selection
             a.SelectAll();
             rtb.SelectedRtf = a.SelectedRtf;
         }
     }
 }

        public string FormattedAnswer()
        {
            RichTextBox rtb = new RichTextBox();
            rtb.Text = Answer;
            rtb.Font = new Font("Segoe UI", 10);

            if (IsCorrect) {
                rtb.Select(0, Answer.Length);
                rtb.SelectionColor = Color.Green;
                rtb.SelectionAlignment = HorizontalAlignment.Center;
                rtb.DeselectAll();
                return rtb.Rtf;
            }

            rtb.Text += " " + RightAnswer;
            rtb.Select(0, Answer.Length);
            rtb.SelectionFont = new Font(rtb.SelectionFont, FontStyle.Strikeout);
            rtb.Select(Answer.Length + 1, RightAnswer.Length);
            rtb.SelectionColor = Color.Green;
            rtb.SelectAll();
            rtb.SelectionAlignment = HorizontalAlignment.Center;
            rtb.DeselectAll();

            return rtb.Rtf;
        }

        /// <summary>
        /// Compares two spells
        /// </summary>
        /// <param name="rtb1">RichTextBox 1 in left</param>
        /// <param name="rtb2">RichTextBox 2 in right</param>
        /// <param name="spell1">Compare Spell 1</param>
        /// <param name="spell2">Compare Spell 2</param>
        public SpellCompare(RichTextBox rtb1, RichTextBox rtb2, SpellInfoHelper spell1, SpellInfoHelper spell2)
        {
            new SpellInfo(rtb1, spell1);
            new SpellInfo(rtb2, spell2);

            var strsl = rtb1.Text.Split('\n');
            var strsr = rtb2.Text.Split('\n');

            var pos = 0;
            foreach (var str in strsl)
            {
                pos += str.Length + 1;
                rtb1.Select(pos - str.Length - 1, pos - 1);

                if (rtb2.Find(str, RichTextBoxFinds.WholeWord) != -1)
                    rtb1.SelectionBackColor = str.ContainsText(_words) ? rtb1.BackColor : Color.Cyan;
                else
                    rtb1.SelectionBackColor = Color.Salmon;
            }

            pos = 0;
            foreach (var str in strsr)
            {
                pos += str.Length + 1;
                rtb2.Select(pos - str.Length - 1, pos - 1);

                if (rtb1.Find(str, RichTextBoxFinds.WholeWord) != -1)
                    rtb2.SelectionBackColor = str.ContainsText(_words) ? rtb2.BackColor : Color.Cyan;
                else
                    rtb2.SelectionBackColor = Color.Salmon;
            }
        }

 /// <summary>
 /// 在富文本上打印消息
 /// </summary>
 /// <param name="richTextBox1">所在打印的富文本</param>
 /// <param name="color">打印字体颜色</param>
 /// <param name="text">要打印的文本</param>
 /// <param name="AutoTime">是否在每条打印结果前追加时间</param>
 public void AppendMsg(RichTextBox richTextBox1, Color color, string text,bool AutoTime)
 {
     richTextBox1.BeginInvoke(new ThreadStart(() =>
      {
          lock (richTextBox1)
          {
              //为控件输入焦点
              richTextBox1.Focus();
              //检查文本框过长
              if (richTextBox1.TextLength > 100000 )
              {
                  richTextBox1.Clear();
              }
              //得到有格式的文本
              using (var temp = new RichTextBox())
              {
                  temp.SelectionColor = color;
                  if (AutoTime)
                      temp.AppendText(DateTime.Now.ToString("yyyyMMdd HH:mm:ss"));
                  temp.AppendText(text);
                  //追加文本
                  richTextBox1.Select(richTextBox1.Rtf.Length, 0);
                  richTextBox1.SelectedRtf = temp.Rtf;
              }
              //设定光标所在位置
              //richTextBox1.SelectionStart = richTextBox1.TextLength;
              //滚动到当前光标处
              //richTextBox1.ScrollToCaret();
          }
      }));
 }

        /// <summary>
        ///  Uses Roslyn technology to build a syntax tree from, and acquire
        ///  diagnostics about, the source code. 
        ///  Diagnostics are rendered into the rich text box. If the compiler
        ///  has highlighted a non-empty span then it is highlighted otherwise
        ///  a red X is display at the error pixel point of an empty span.
        /// </summary>
        /// <param name="tbSource">Text box with C# source code.</param>
        /// <param name="richResult">Rich text box to render syntax highlighting into.</param>
        /// <remarks>
        /// Only the first source code syntax error is highlighted. 
        /// </remarks>
        static void BuildSyntaxView(TextBox tbSource, RichTextBox richResult)
        {
            richResult.Text = tbSource.Text;

            // Roslyn!! - SyntaxTree.*
            var syntaxTree = SyntaxTree.ParseText(tbSource.Text);

            var diags = syntaxTree.GetDiagnostics();

            // Display all compiler diagnostics in console
            Console.WriteLine("============================");
            Console.WriteLine("Compiler has {0} diagnostic messages.", diags.Count());
            // Roslyn again!!
            foreach (var d in diags)
                Console.WriteLine("> {0}", d.Info.GetMessage());
            Console.WriteLine("-------------------------");

            List<Point> issuePoints = new List<Point>();
            picX.Visible = false;

            foreach (var d in diags)
            {
                // More Roslyn !! - d.*
                if (d.Location.IsInSource)
                {
                    var origFore = Console.ForegroundColor;
                    var origBack = Console.BackgroundColor;

                    Console.BackgroundColor = ConsoleColor.Red;
                    Console.ForegroundColor = ConsoleColor.Black;
                    Console.Write(tbSource.Text.Substring(d.Location.SourceSpan.Start, d.Location.SourceSpan.Length));

                    // Hey Roslyn !! - d.*
                    int lineEndOffset = d.Location.GetLineSpan(true).StartLinePosition.Line;
                    // Note: line endings in rich text box use one character where textbox input source uses two
                    richResult.Select(d.Location.SourceSpan.Start - lineEndOffset, d.Location.SourceSpan.Length);
                    richResult.SelectionColor = Color.Yellow;
                    richResult.SelectionBackColor = Color.Red;
                    if (d.Location.SourceSpan.Length == 0)
                        issuePoints.Add(richResult.GetPositionFromCharIndex(d.Location.SourceSpan.Start));

                    Console.BackgroundColor = origBack;
                    Console.ForegroundColor = origFore;

                    Console.WriteLine(tbSource.Text.Substring(d.Location.SourceSpan.Start + d.Location.SourceSpan.Length));
                    break; // Stop after first error is highlighted
                    // No dealing with multiple errors or overlaps in this sample.
                }
            }

            // Put the X on the first error
            if (issuePoints.Count != 0)
            {
                picX.Location = issuePoints[0];
                picX.Visible = true;
            }

            Console.WriteLine("============================");
        }

 public void appendTextBox(RichTextBox textBox, string strInput, Color fontColor, Font fontType)
 {
     int p1 = textBox.TextLength;            //取出未添加时的字符串长度
     textBox.AppendText(strInput);           //保留每行的所有颜色
     int p2 = strInput.Length;               //取出要添加的文本的长度
     textBox.Select(p1, p2);                 //选中要添加的文本
     textBox.SelectionColor = fontColor;     //设置要添加的文本的字体色
     textBox.SelectionFont = fontType;       //设置要添加的文本的字体
 }

 void AppendText(RichTextBox box, Color color, string text)
 {
     int start = box.TextLength;
     box.AppendText(text);
     int end = box.TextLength;
     box.Select(start, end-start);
     box.SelectionColor = color;
     box.SelectionLength = 0;
 }

        public static void ChangeFontStyle(FontStyle style, RichTextBox richTextBox1)
        {
            if (style != FontStyle.Bold && style != FontStyle.Italic &&
                style != FontStyle.Underline)
                throw new System.InvalidProgramException("字体格式错误");
            RichTextBox tempRichTextBox = new RichTextBox();  //将要存放被选中文本的副本  
            int curRtbStart = richTextBox1.SelectionStart;
            int len = richTextBox1.SelectionLength;
            int tempRtbStart = 0;
            Font font = richTextBox1.SelectionFont;
            if (len <= 1 && font != null) //与上边的那段代码类似，功能相同  
            {
                if (style == FontStyle.Bold && font.Bold ||
                    style == FontStyle.Italic && font.Italic ||
                    style == FontStyle.Underline && font.Underline)
                {
                    richTextBox1.SelectionFont = new Font(font, font.Style ^ style);
                }
                else if (style == FontStyle.Bold && !font.Bold ||
                         style == FontStyle.Italic && !font.Italic ||
                         style == FontStyle.Underline && !font.Underline)
                {
                    richTextBox1.SelectionFont = new Font(font, font.Style | style);
                }
                return;
            }
            tempRichTextBox.Rtf = richTextBox1.SelectedRtf;
            tempRichTextBox.Select(len - 1, 1); //选中副本中的最后一个文字  
            //克隆被选中的文字Font，这个tempFont主要是用来判断  
            //最终被选中的文字是否要加粗、去粗、斜体、去斜、下划线、去下划线  
            Font tempFont = (Font)tempRichTextBox.SelectionFont.Clone();

            //清空2和3  
            for (int i = 0; i < len; i++)
            {
                tempRichTextBox.Select(tempRtbStart + i, 1);  //每次选中一个，逐个进行加粗或去粗  
                if (style == FontStyle.Bold && tempFont.Bold ||
                    style == FontStyle.Italic && tempFont.Italic ||
                    style == FontStyle.Underline && tempFont.Underline)
                {
                    tempRichTextBox.SelectionFont =
                        new Font(tempRichTextBox.SelectionFont,
                                 tempRichTextBox.SelectionFont.Style ^ style);
                }
                else if (style == FontStyle.Bold && !tempFont.Bold ||
                         style == FontStyle.Italic && !tempFont.Italic ||
                         style == FontStyle.Underline && !tempFont.Underline)
                {
                    tempRichTextBox.SelectionFont =
                        new Font(tempRichTextBox.SelectionFont,
                                 tempRichTextBox.SelectionFont.Style | style);
                }
            }
            tempRichTextBox.Select(tempRtbStart, len);
            richTextBox1.SelectedRtf = tempRichTextBox.SelectedRtf; //将设置格式后的副本拷贝给原型  
            richTextBox1.Select(curRtbStart, len);
        }

        public static void AppendInternal(RichTextBox richTextBox, Color colorFore, Color colorBack, FontStyle newStyle, string text)
        {
            if(richTextBox != null && !string.IsNullOrEmpty(text) && !richTextBox.IsDisposed)
            {
                if(richTextBox.InvokeRequired)
                {
                    richTextBox.BeginInvoke(new MethodInvoker(delegate() { AppendInternal(richTextBox, colorFore, colorBack, newStyle, text); }));
                }
                else
                {
                    lock(richTextBox)
                    {
                        richTextBox.SuspendLayout();

                        //Truncate as necessary
                        if(richTextBox.Text.Length + text.Length > _maxConsoleTextLength)
                        {
                            int truncateLength = _maxConsoleTextLength / 4;
                            int endmarker = richTextBox.Text.IndexOf('\n', truncateLength) + 1;
                            if(endmarker < truncateLength)
                                endmarker = truncateLength;
                            richTextBox.Select(0, endmarker);
                            richTextBox.Cut();
                        }

                        int originalTextEnd = richTextBox.Text.Length;
                        richTextBox.AppendText(text);
                        richTextBox.Select(originalTextEnd, text.Length);
                        if(colorFore != Color.Empty)
                            richTextBox.SelectionColor = colorFore;
                        if(colorBack != Color.Empty)
                            richTextBox.SelectionBackColor = colorBack;

                        //if(newStyle != richTextBox.Font.Style)
                        richTextBox.SelectionFont = new Font(richTextBox.Font, newStyle);

                        richTextBox.SelectionLength = 0;
                        richTextBox.ScrollToCaret();
                        richTextBox.ResumeLayout();
                        richTextBox.Update();
                    }
                }
            }
        }

        string[] words = new[] { "=====" }; // todo: more wodrs

        #endregion Fields

        #region Constructors

        /// <summary>
        /// Compares two spells
        /// </summary>
        /// <param name="rtb1">RichTextBox 1 in left</param>
        /// <param name="rtb2">RichTextBox 2 in right</param>
        /// <param name="spell1">Compare Spell 1</param>
        /// <param name="spell2">Compare Spell 2</param>
        public SpellCompare(RichTextBox rtb1, RichTextBox rtb2, SpellEntry spell1, SpellEntry spell2)
        {
            new SpellInfo(rtb1, spell1);
            new SpellInfo(rtb2, spell2);

            string[] strsl = rtb1.Text.Split('\n');
            string[] strsr = rtb2.Text.Split('\n');

            int pos = 0;
            foreach (string str in strsl)
            {
                pos += str.Length + 1;
                rtb1.Select(pos - str.Length - 1, pos - 1);

                if (rtb2.Find(str, RichTextBoxFinds.WholeWord) != -1)
                {
                    if (str.ContainsText(words))
                    {
                        rtb1.SelectionBackColor = rtb1.BackColor;
                    }
                    else
                    {
                        rtb1.SelectionBackColor = Color.Cyan;
                    }
                }
                else
                {
                    rtb1.SelectionBackColor = Color.Salmon;
                }
            }

            pos = 0;
            foreach (string str in strsr)
            {
                pos += str.Length + 1;
                rtb2.Select(pos - str.Length - 1, pos - 1);

                if (rtb1.Find(str, RichTextBoxFinds.WholeWord) != -1)
                {
                    if (str.ContainsText(words))
                    {
                        rtb2.SelectionBackColor = rtb2.BackColor;
                    }
                    else
                    {
                        rtb2.SelectionBackColor = Color.Cyan;
                    }
                }
                else
                {
                    rtb2.SelectionBackColor = Color.Salmon;
                }
            }
        }

 void AppendText(RichTextBox box, Color color, string text)
 {
     int start = box.TextLength;
     box.AppendText(text + Environment.NewLine);
     int end = box.TextLength;
     box.Select(start, end - start);
     {
         box.SelectionColor = color;
     }
     box.SelectionLength = 0;
 }

        internal static void Update(RichTextBox box)
        {
            if (appendQueue.IsEmpty) return;

            var start = box.SelectionStart;
            var len = box.SelectionLength;
            var scroll = box.TextLength == start;

            LogLine result;
            box.Select(box.TextLength, 0);
            while (appendQueue.TryDequeue(out result)) {
                box.SelectionColor = result.color;
                box.AppendText(result.line+"\r\n");
                writer.WriteLine(result.line);
                lines++;
            }
            writer.Flush();

            if (lines > maxLines) {
                box.ReadOnly = false;
                while (lines > maxLines) {
                    var lineLen = box.Text.IndexOf('\n') + 1;
                    box.Select(0, lineLen);
                    box.Cut();
                    start -= lineLen;
                    lines--;
                }
                box.ReadOnly = true;
            }

            if (scroll) {
                box.Select(box.TextLength, 0);
                box.ScrollToCaret();
            } else if (start + len > 0) {
                if (start < 0) {
                    len += start;
                    start = 0;
                }
                box.Select(start, len);
            }
        }

 private void AppendTextWithGivenColor(RichTextBox box, Color color, string text)
 {
     int start = box.TextLength;
     box.AppendText(text);
     int end = box.TextLength;
     box.Select(start, end - start);
     {
         box.SelectionColor = color;
         // could set box.SelectionBackColor, box.SelectionFont too.
     }
     box.SelectionLength = 0; // clear
 }

		public static void applyStyleToTextbox(BBCodeStyle style, RichTextBox tf, int selStart, int selEnd)
		{
			if (style == null || tf == null || selEnd <= selStart || selEnd < 0)
				return;

			tf.Select(selStart, selEnd);

			FontStyle fontStyle = tf.Font.Style;
			String fontName = tf.Font.Name;
			float fontSize = tf.Font.Size;


			if (style.isBold == StateMode.ON)
				fontStyle |= FontStyle.Bold;
			else if (style.isBold == StateMode.OFF)
				fontStyle &= ~FontStyle.Bold;

			if (style.isItalic == StateMode.ON)
				fontStyle |= FontStyle.Italic;
			else if (style.isItalic == StateMode.OFF)
				fontStyle &= ~FontStyle.Italic;

			if (style.isUnderlined == StateMode.ON)
				fontStyle |= FontStyle.Underline;
			else if (style.isUnderlined == StateMode.OFF)
				fontStyle &= ~FontStyle.Underline;

			if (style.isStriked == StateMode.ON)
				fontStyle |= FontStyle.Strikeout;
			else if (style.isStriked == StateMode.OFF)
				fontStyle &= ~FontStyle.Strikeout;


			if (style.fontSize > 0)
				fontSize = (float)style.fontSize;
			else if (style.fontSize < 0)
				fontSize += (float)style.fontSize;

			if (style.fontName != null && style.fontName.Length > 0)
				fontName = style.fontName;


			if (style.foreColor != null)
				tf.SelectionColor = Color.FromArgb((int)((uint)(0xFF000000) | (uint)(style.foreColor.color & 0xFFFFFF)));

			if (style.backColor != null)
				tf.SelectionBackColor = Color.FromArgb((int)((uint)(0xFF000000) | (uint)(style.backColor.color & 0xFFFFFF)));


			Font font = new Font(fontName, (float)(fontSize > 1.0f ? fontSize : 1.0f), fontStyle);
			tf.SelectionFont = font;
		}