Question

Basically I want to read and write to a file then save all the compiled content another file.

Steps:

1. Say I have a file mycode.js with this code:

     var url = '';     //this will be field throug form in php
   

2. Now in php, I will input a value of that url e.g www.google.com

3. How will I be able to append the url I just entered to my js file?
   Expected output:

   var url = 'www.google.com';
   

4. Also follow question, upon successful append of the value to my JS file I will now create a new file (newlyappend.js), like a save as thing. Where the content of the file is the newly append code:

   var url = 'www.google.com';
   

Would like to achieve this using php.

Answer 1

Get the .js file content as a string:

$js = file_get_contents( '/path/to/file/mycode.js' );

$js will now hold the content of the file.

Replace the empty variable line with a value assignment:

$url = 'www.google.com';
$js = str_replace( "var url = '';", "var url = '$url';", $js );

Write the new content back to a new js file:

file_put_contents( '/path/to/file/newlyappend.js', $js );

Make sure you have proper permissions to read & write files from the specified paths.