选择性着色文本RichTextBox中

Question

我怎样才能在红色每当我满足RichTextBox的字母“A”的时间画画吗？

Answer 1

试试这个：

static void HighlightPhrase(RichTextBox box, string phrase, Color color) { 
    int pos = box.SelectionStart; 
    string s = box.Text; 
    for (int ix = 0; ;) { 
    int jx = s.IndexOf(phrase, ix, StringComparison.CurrentCultureIgnoreCase); 
    if (jx < 0) break; 
    box.SelectionStart = jx; 
    box.SelectionLength = phrase.Length; 
    box.SelectionColor = color; 
    ix = jx + 1; 
    } 
    box.SelectionStart = pos; 
    box.SelectionLength = 0; 
} 

...

private void button1_Click(object sender, EventArgs e) { 
    richTextBox1.Text = "Aardvarks are strange animals"; 
    HighlightPhrase(richTextBox1, "a", Color.Red); 
} 

Answer 2

，而你是打字，如果这是你在找什么这不会工作，但我用这个来突出子：

Function Highlight(ByVal Search_Str As Object, ByVal InputTxt As String, ByVal StartTag As String, ByVal EndTag As String) As String 
    Highlight = Regex.Replace(InputTxt, "(" & Regex.Escape(Search_Str) & ")", StartTag & "$1" & EndTag, RegexOptions.IgnoreCase) 
End Function 

，并调用它是这样的：

 
Highlight("A", "Color All my A's red", [span class=highlight]', '[/span]') 

其中班级'突出'具有任何颜色编码/格式你想要的：

 
.highlight {text-decoration: none;color:black;background:red;} 

顺便说一句：你需要改变th OSE方括号弯角的...他们不会来了直通当我键入他们...

Answer 3

这是C＃为EJ布伦南的答案代码：

public string Highlight(object Search_Str, string InputTxt, string StartTag, string EndTag) 
{ 
    return Regex.Replace(InputTxt, "(" + Regex.Escape(Search_Str) + ")", StartTag + "$1" + EndTag, RegexOptions.IgnoreCase); 
} 

Answer 4

这里是一个片段从我的包装类的做这个工作：

private delegate void AddMessageCallback(string message, Color color); 

    public void AddMessage(string message) 
    { 
     Color color = Color.Empty; 

     string searchedString = message.ToLowerInvariant(); 

     if (searchedString.Contains("failed") 
      || searchedString.Contains("error") 
      || searchedString.Contains("warning")) 
     { 
      color = Color.Red; 
     } 
     else if (searchedString.Contains("success")) 
     { 
      color = Color.Green; 
     } 

     AddMessage(message, color); 
    } 

    public void AddMessage(string message, Color color) 
    { 
     if (_richTextBox.InvokeRequired) 
     { 
      AddMessageCallback cb = new AddMessageCallback(AddMessageInternal); 
      _richTextBox.BeginInvoke(cb, message, color); 
     } 
     else 
     { 
      AddMessageInternal(message, color); 
     } 
    } 

    private void AddMessageInternal(string message, Color color) 
    { 
     string formattedMessage = String.Format("{0:G} {1}{2}", DateTime.Now, message, Environment.NewLine); 

     if (color != Color.Empty) 
     { 
      _richTextBox.SelectionColor = color; 
     } 
     _richTextBox.SelectedText = formattedMessage; 

     _richTextBox.SelectionStart = _richTextBox.Text.Length; 
     _richTextBox.ScrollToCaret(); 
    } 

现在您可以使用AddMessage("The command failed")来调用它，以红色自动突出显示。或者你可以用AddMessage("Just a special message", Color.Purple)调用它来定义一个特殊的颜色（catch块内有用例如定义一个特定的颜色，无论邮件内容）