PHP is_writable()Function


PHP Filesystem 参考手册Complete PHP Filesystem Reference Manual

Definition and Usage

The is_writable() function checks whether the specified file is writable.

If the file is writable, the function returns TRUE.

Syntax

is_writable(file)

Parameter Description
file Required. Specifies the file to be checked.


Tips and Notes

Note:The results of this function are cached. Use clearstatcache() to clear the cache.


Example

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

The above code will output:

test.txt is writeable


PHP Filesystem 参考手册Complete PHP Filesystem Reference Manual Other Extensions