Question

I want to remove a dot (.) if appears at the start of the line, so for example:

hi,
<new line> .
<new line> How are you.

How can I remove this line?

Answer 1

Remove a dot at the start of a line:

resultString = Regex.Replace(subjectString, @"^\.", "", RegexOptions.Multiline);

Remove an entire line if it starts with a dot:

resultString = Regex.Replace(subjectString, @"^\..*\r\n", "", RegexOptions.Multiline);

Remove an entire line if it contains only a dot:

resultString = Regex.Replace(subjectString, @"^\.\r\n", "", RegexOptions.Multiline);

Remove an entire line if it starts with a dot and possibly contains trailing whitespace:

resultString = Regex.Replace(subjectString, @"^\.[^\r\n\S]*\r\n", "", RegexOptions.Multiline);