[regex] How to check if a line is blank using regex

I am trying to make simple regex that will check if a line is blank or not.

Case;

"    some"   // not blank
"   " //blank
"" // blank

Well...I tinkered around (using notepadd++) and this is the solution I found

\n\s

\n for end of line (where you start matching) -- the caret would not be of help in my case as the beginning of the row is a string \s takes any space till the next string

hope it helps

The most portable regex would be ^[ \t\n]*$ to match an empty string (note that you would need to replace \t and \n with tab and newline accordingly) and [^ \n\t] to match a non-whitespace string.

Try this:

^\s*$

Full credit to bchr02 for this answer. However, I had to modify it a bit to catch the scenario for lines that have */ (end of comment) followed by an empty line. The regex was matching the non empty line with */.

New: (^(\r\n|\n|\r)$)|(^(\r\n|\n|\r))|^\s*$/gm

All I did is add ^ as second character to signify the start of line.

Here Blank mean what you are meaning.
A line contains full of whitespaces or a line contains nothing.
If you want to match a line which contains nothing then use '/^$/'.

Actually in multiline mode a more correct answer is this:

/((\r\n|\n|\r)$)|(^(\r\n|\n|\r))|^\s*$/gm

The accepted answer: ^\s*$ does not match a scenario when the last line is blank (in multiline mode).