Notepad++ - Merge all lines into one and add separator

So this is my situation: I have a lot of lines like this:

line1
     line2
              line3
     line4

And they all start with different spaces. What I want to do is merge all the lines in the document into one, but separate each one with some character, something like this:

line1 | line2 | line3 | line4

How can I do this?

Solution 1:

No regex required in this case.

1. Edit > Blank Operations > Trim leading Space.

2. Replace All "\r\n" with " | " (make sure Extended Search Mode is selected):

   

Solution 2:

As @Karan answers regex it's not necessary to solve your question, anywise you can use it to do it in one step and to avoid errors with different UNIX/Windows end lines (\n or \r\n).

To do so you can use the Replace All "\s*(.+)\s+" with "$1 | " with Regular Expression mode selected: