public static function recursiveDelete($dir)
{
    foreach (new \DirectoryIterator($dir) as $fileInfo) {
        if (!$fileInfo->isDot()) {
            if ($fileInfo->isDir()) {
                recursiveDelete($fileInfo->getPathname());
            } else {
                unlink($fileInfo->getPathname());
            }
        }
    }
    rmdir($dir);
}

如果你想删除文件夹中的所有内容(包括子文件夹)，请使用array_map, unlink和glob的组合:

array_map( 'unlink', array_filter((array) glob("path/to/temp/*") ) );

这个调用还可以处理空目录(感谢您的提示，@mojuba!)

以下代码来自http://php.net/unlink:

/**
 * Delete a file or recursively delete a directory
 *
 * @param string $str Path to file or directory
 */
function recursiveDelete($str) {
    if (is_file($str)) {
        return @unlink($str);
    }
    elseif (is_dir($str)) {
        $scan = glob(rtrim($str,'/').'/*');
        foreach($scan as $index=>$path) {
            recursiveDelete($path);
        }
        return @rmdir($str);
    }
}

我更新了@Stichoza的答案，通过子文件夹删除文件。

function glob_recursive($pattern, $flags = 0) {
    $fileList = glob($pattern, $flags);
    foreach (glob(dirname($pattern).'/*', GLOB_ONLYDIR|GLOB_NOSORT) as $dir) {
        $subPattern = $dir.'/'.basename($pattern);
        $subFileList = glob_recursive($subPattern, $flags);
        $fileList = array_merge($fileList, $subFileList);
    }
    return $fileList;
}

function glob_recursive_unlink($pattern, $flags = 0) {
    array_map('unlink', glob_recursive($pattern, $flags));
}

下面是一种使用标准PHP库(SPL)的更现代的方法。

$dir = "path/to/directory";
if(file_exists($dir)){
    $di = new RecursiveDirectoryIterator($dir, FilesystemIterator::SKIP_DOTS);
    $ri = new RecursiveIteratorIterator($di, RecursiveIteratorIterator::CHILD_FIRST);
    foreach ( $ri as $file ) {
        $file->isDir() ?  rmdir($file) : unlink($file);
    }
}

 <?
//delete all files from folder  & sub folders
function listFolderFiles($dir)
{
    $ffs = scandir($dir);
    echo '<ol>';
    foreach ($ffs as $ff) {
        if ($ff != '.' && $ff != '..') {
            if (file_exists("$dir/$ff")) {
                unlink("$dir/$ff");
            }
            echo '<li>' . $ff;
            if (is_dir($dir . '/' . $ff)) {
                listFolderFiles($dir . '/' . $ff);
            }
            echo '</li>';
        }
    }
    echo '</ol>';
}
$arr = array(
    "folder1",
    "folder2"
);
for ($x = 0; $x < count($arr); $x++) {
    $mm = $arr[$x];
    listFolderFiles($mm);
}
//end
?>