is_writable

Definition and usage

is_writable() function determines whether the specified file is writable.

实例

<?php
$file = "test.txt";
if(is_writable($file))
  {
  echo ("$file is writeable");
  }
else
  {
  echo ("$file is not writeable");
  }
?>

输出：

test.txt is writeable

grammar

 is_writable ( file )

illustrate

Return true if the file exists and is writable. The file parameter can be a directory name that allows for writable checks.