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The example in this article describes how PHP calculates the relative paths of two files. Share it with everyone for your reference. The details are as follows:
1. Question:
Write a php function to calculate the relative paths of two files. For example, $a="/a/b/c/d/e.php"; $b="/a/b/12/34/c.php", what is the relative path of B relative to A?
2. Solution:
<?php /** * 求$b相对于$a的相对路径 * @param string $a * @param string $b * @return string */ function getRelativePath ($a, $b) { $patha = explode('/', $a); $pathb = explode('/', $b); $counta = count($patha) - 1; $countb = count($pathb) - 1; $path = "../"; if ($countb > $counta) { while ($countb > $counta) { $path .= "../"; $countb --; } } // 寻找第一个公共结点 for ($i = $countb - 1; $i >= 0;) { if ($patha[$i] != $pathb[$i]) { $path .= "../"; $i --; } else { //判断是否为真正的第一个公共结点,防止出现子目录重名情况 for ($j = $i - 1, $flag = 1; $j >= 0; $j --) { if ($patha[$j] == $pathb[$j]) { continue; } else { $flag = 0; break; } } if ($flag) break; else $i ++; } } for ($i += 1; $i <= $counta; $i ++) { $path .= $patha[$i] . "/"; } return $path; } $a = "/a/c/d/e.php"; $b = "/a/c.php"; $path = getRelativePath($a, $b); echo $path;
I hope this article will be helpful to everyone’s PHP programming design.