php源碼之計算兩個文件的相對路徑，
<?php
//計算出兩個文件的相對路徑即path2相對於$path1的相對路徑
// http://www.manongjc.com/article/1342.html
function get_relative_path($path1,$path2){
$arr1 = explode(DIRECTORY_SEPARATOR,dirname($path1));
$arr2 = explode(DIRECTORY_SEPARATOR,dirname($path2));
$length = count($arr2);
for($i = 0; $i < $length; $i++){
if($arr1[$i] != $arr2[$i]){ //進行路徑匹配
break;
}
}
if($i == 0){ //根目錄不同
return '不在同一個目錄中';
}else if($i != 0 && $i < $length){ //在同一個個目錄下
$separator = array_fill(0, ($length-$i), '..');
return(implode(DIRECTORY_SEPARATOR, array_merge($separator, array_slice($arr1, $i))));
}else if($i == $length){ //路徑完全相同 http://www.manongjc.com/article/1343.html
return '.';
}
}
$path1 = 'F:\Apache\www\temp\php_demo\demo.md'; //參照路徑path1
$path2 = 'F:\Apache\www\temp\php_demo\demo.md';
$path3 = 'F:\Apache\www\temp\sd\ss.d\sdsfd';
$path4 = 'G:\FFOutput';
var_dump(get_relative_path($path1,$path2));
var_dump(get_relative_path($path1,$path3));
var_dump(get_relative_path($path1,$path4));
?>
