Question

I want to add a string (the value of a DOM element – $entry = stripslashes($_GET["nameofmytextarea"]);) to the second line of myfile.csv (so as not to delete the header).

I don’t care about CSV stuff, everything is already formatted. Just treat it as a text string being added to a text file.

I don’t want anything complicated, just skip the first line and “append” above the second line: under the header but above all the other CSV lines.

How hard can that be?

Answer 1

$contents = explode("\n", file_get_contents('myfile.csv'), 2);
file_put_contents('myfile.csv', $contents[0]."\n".$entry."\n".$contents[1]);

This should work if the lines are separated by unix-lineendings.
If the file first looks like this:

header
content
content2

and the code is run with $entry = 'test'; it will look like this afterwards:

header
test
content
content2