How does PHP create a file and write text?

PHP: how to create a file and write text? I want to encapsulate a method to create a file and write two width and height parameters to the text.

Effect after implementation
For example, 100 300

The generated file name is s 100300. less.

The content is
@ Import "shiying ";
@ Screen_width: 100px;
@ Screen_height: 300px;


How to write this function .. Red must match

Reply to discussion (solution)

function mkless($width, $height) {  $r[] = '@import "shiying";';  $r[] = sprintf('@screen_width:%spx;', $width);  $r[] = sprintf('@screen_height:$spx;', $height);  file_put_contents("s$width$height.less", join(PHP_EOL, $r));}

function mkless($width, $height) {  $r[] = '@import "shiying";';  $r[] = sprintf('@screen_width:%spx;', $width);  $r[] = sprintf('@screen_height:$spx;', $height);  file_put_contents("s$width$height.less", join(PHP_EOL, $r);}

Parse error: syntax error, unexpected ';' in D: \ wamp \ www \ ceshi \ xieru. php on line 14
An error is reported, and the fileputcontent cannot generate files automatically ..

File_put_contents ("s $ width $ height. less", join (PHP_EOL, $ r );
Parentheses

The file_put_contents () function writes a string to a file.

It is the same as calling the fopen (), fwrite (), and fclose () functions in turn.
Syntax

File_put_contents (file, data, mode, context)

Parameter description
File is required. Specifies the file to write data. If the file does not exist, create a new file.
....
...

Is a function call problem.

File_put_contents

By the way, the code

$filename='s100300.less';$date='@import "shiying";@screen_width:100px;@screen_height:300px;';file_put_contents($filename,$date);