WPF RichTextBox：如何在Run（text）的单个句子中添加不同的颜色？

Question

I have a client talking to a server. The server may may send back the buffer as "Bob: Is anyone here?" You can think of it like a chatroom.

Prior to the first occurrence of ':', I would like to make this word green. Everything to the right of ':' will stay white.

How can I do this? I found this not to be so straight-forward.

This writes an incoming text message to the RichTextBox:

public void WriteLine(string text)
{
    Paragraph para = new Paragraph(); 

    // Buffer output
    para.Inlines.Add(new Run(text));

    // Add block
    txtOutput.Document.Blocks.Add(para);

    // Always keep scrolled to the end
    txtOutput.ScrollToEnd();

    // Clear input field.
    txtInput.Clear();

    // Focus back on the input field.
    txtInput.Focus();
}

My attempt:

// Output buffer
para.Inlines.Add(new Run { Text = text, Foreground = Brushes.Green, FontWeight = FontWeights.Bold });

The problem with doing it this way is the whole line will be green. What I need is this format:

Name (Green): Output (White).

Please let me know. Thanks.

Answer 1

Prior to the first occurrence of ':', I would like to make this word green. Everything to the right of ':' will stay white.

Based on your requirement in question, all you need to do is to split the text and add two Run to your Paragraph.

Check the below code.

public void WriteLine(string text)
{
    Paragraph para = new Paragraph();

    //Split the content from text

    var content = text.Split(':');

    // Buffer output
    para.Inlines.Add(new Run { Text = content[0] + ": ", Foreground = Brushes.Green, FontWeight = FontWeights.Bold });
    para.Inlines.Add(new Run { Text = content[1], Foreground = Brushes.White, FontWeight = FontWeights.Regular });

    // Add block
    txtOutput.Document.Blocks.Add(para);

    // Always keep scrolled to the end
    txtOutput.ScrollToEnd();

    //// Clear input field.
    //txtInput.Clear();

    //// Focus back on the input field.
    //txtInput.Focus();
}