首页 / 网页编程 / PHP / php从文件夹随机读取文件的方法

function RandomFile（$folder="", $extensions=".*"）{// fix path:$folder = trim（$folder）;$folder = （$folder == ""） ? "./" : $folder;// check folder:if （！is_dir（$folder））{ die（"invalid folder given！"）; }// create files array$files = array（）;// open directoryif （$dir = @opendir（$folder））{// go trough all files:while（$file = readdir（$dir））{if （！preg_match（"/^.+$/", $file） and preg_match（"/.（".$extensions."）$/", $file））{// feed the array:$files[] = $file;}}// close directoryclosedir（$dir）;}else {die（"Could not open the folder "".$folder."""）;}if （count（$files） == 0）{die（"No files where found :-（"）;}// seed random function:mt_srand（（double）microtime（）*1000000）;// get an random index:$rand = mt_rand（0, count（$files）-1）;// check again:if （！isset（$files[$rand]））{die（"Array index was not found！ very strange！"）;}// return the random file:return $folder . $files[$rand];}//用法演示：// "jpg|png|gif" matches all files with these extensionsprint RandomFile（"test_images/","jpg|png|gif"）;// returns test_07.gif// ".*" matches all extensions （all files）print RandomFile（"test_files/",".*"）;// returns foobar_1.zip// "[0-9]+" matches all extensions that just // contain numbers （like backup.1, backup.2）print RandomFile（"test_files/","[0-9]+"）;// returns backup.7