How to insert double backslash

[KangaBytes]

I need to, find out how I can, have a double backslash  \\  before various characters like quotation marks.

I need this, as I use the echo keyword, to create JSON, for a website of mine.

Now, I have spent hours experimenting, and so on, and the following is what I have done.....

When I use  addslashes($a), I get one backslash each time,  when I nest one inside the other like addslashes(addslashes($a)), I get three each time.

Both times, the JSON parse operator rejected the input.

The only option that the JSON parse operator would accept is, when I had two backslashes.  That worked out perfectly fine.

At the same time, if I may ask this in this forum, I will be happy to accept any javascript solution of which you want to put forward to me here too.  I just have JSON.parse(....responseText) on that end.

[Barand]

17 minutes ago, KangaBytes said:

I need to, find out how I can, have a double backslash  \\  before various characters like quotation marks.

Why?

$str = "The man from Del Monte, he said \"Yes!\"";
$j = json_encode($str);

echo $j . '<br>';                    //  "The man from Del Monte, he said \"Yes!\""

echo json_decode($j);                //  The man from Del Monte, he said "Yes!"