I think for that you need rich textbox control
Example :
public void CreateMyRichTextBox()
{
RichTextBox richTextBox1 = new RichTextBox();
richTextBox1.Dock = DockStyle.Fill;
richTextBox1.LoadFile("C:\\MyDocument.rtf");
richTextBox1.Find("Text", RichTextBoxFinds.MatchCase);
richTextBox1.SelectionFont = new Font("Verdana", 12, FontStyle.Bold);
richTextBox1.SelectionColor = Color.Red;
richTextBox1.SaveFile("C:\\MyDocument.rtf", RichTextBoxStreamType.RichText);
this.Controls.Add(richTextBox1);
}
and for more details see the links that is listed below...
Link1[
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Link2[
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Link3[
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