Color specific words in RichtextBox
c#, winforms
Solution
Add an event to your rich box text changed,
private void Rchtxt_TextChanged(object sender, EventArgs e)
{
this.CheckKeyword("while", Color.Purple, 0);
this.CheckKeyword("if", Color.Green, 0);
}
private void CheckKeyword(string word, Color color, int startIndex)
{
if (this.Rchtxt.Text.Contains(word))
{
int index = -1;
int selectStart = this.Rchtxt.SelectionStart;
while ((index = this.Rchtxt.Text.IndexOf(word, (index + 1))) != -1)
{
this.Rchtxt.Select((index + startIndex), word.Length);
this.Rchtxt.SelectionColor = color;
this.Rchtxt.Select(selectStart, 0);
this.Rchtxt.SelectionColor = Color.Black;
}
}
}
Problem
How can I make, that when the user types specific words like 'while' or 'if' in a rich textbox, the words will color purple without any problems? I've tried diffrent codes, but none of them were usable. The codes were like below: ``` if (richTextBox.Text.Contains("while")) { richTextBox.Select(richTextBox.Text.IndexOf("while"), "while".Length); richTextBox.SelectionColor = Color.Aqua; } ``` Also, I want that when the user removes the word or removes a letter from the word, the word will color back to its default color. I'm making a program with a code editor in it. I am using Visual c#. Thank you.