/
****php常用函数
/
1、加密解密字符串
function encryptDecrypt($key, $string, $decrypt){
if($decrypt){
$decrypted = rtrim(mcrypt_decrypt(MCRYPT_RIJNDAEL_256, md5($key), base64_decode($string), MCRYPT_MODE_CBC, md5(md5($key))), "12");
return $decrypted;
}else{
$encrypted = base64_encode(mcrypt_encrypt(MCRYPT_RIJNDAEL_256, md5($key), $string, MCRYPT_MODE_CBC, md5(md5($key))));
return $encrypted;
}
}
//以下是将字符串“Helloweba欢迎您”分别加密和解密
//加密：
echo encryptDecrypt(‘password‘, ‘Helloweba欢迎您‘,0);
//解密：
echo encryptDecrypt(‘password‘, ‘z0JAx4qMwcF+db5TNbp/xwdUM84snRsXvvpXuaCa4Bk=‘,1);
2、php生成随机字符串 字母和数字的集合
function generateRandomString($length = 10) {
$characters = ‘0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ‘;
$randomString = ‘‘;
for ($i = 0; $i < $length; $i++) {
$randomString .= $characters[rand(0, strlen($characters) - 1)];
}
return $randomString;
}
3、php获取文件后缀名
function getExtension($filename){
$myext = substr($filename, strrpos($filename, ‘.‘));
return str_replace(‘.‘,‘‘,$myext);
}
4、php获取文件大小并格式化 以下使用的函数可以获取文件的大小，并且转换成便于阅读的KB，MB等格式。
function formatSize($size) {
$sizes = array(" Bytes", " KB", " MB", " GB", " TB", " PB", " EB", " ZB", " YB");
if ($size == 0) {
return(‘n/a‘);
} else {
return (round($size/pow(1024, ($i = floor(log($size, 1024)))), 2) . $sizes[$i]);
}
}
//$thefile = filesize(‘test_file.mp3‘);
5、php替换字符标签
function stringParser($string,$replacer){
$result = str_replace(array_keys($replacer), array_values($replacer),$string);
return $result;
}
$string = ‘The {b}anchor text{/b} is the {b}actual word{/b} or words used {br}to describe the link {br}itself‘;
$replace_array = array(‘{b}‘ => ‘<b>‘,‘{/b}‘ => ‘</b>‘,‘{br}‘ => ‘<br />‘);
echo stringParser($string,$replace_array);
6、php列出文件夹下的所有文件名
function listDirFiles($DirPath){
if($dir = opendir($DirPath)){
while(($file = readdir($dir))!== false){
if(!is_dir($DirPath.$file))
{
echo "filename: $file<br />";
}
}
}
}
//listDirFiles(‘home/some_folder/‘);
7、php获取当前网页的url
function curPageURL() {
$pageURL = ‘http‘;
if (!empty($_SERVER[‘HTTPS‘])) {$pageURL .= "s";}
$pageURL .= "://";
if ($_SERVER["SERVER_PORT"] != "80") {
$pageURL .= $_SERVER["SERVER_NAME"].":".$_SERVER["SERVER_PORT"].$_SERVER["REQUEST_URI"];
} else {
$pageURL .= $_SERVER["SERVER_NAME"].$_SERVER["REQUEST_URI"];
}
return $pageURL;
}
echo curPageURL();
8、php强制下载文件
function download($filename){
if ((isset($filename))&&(file_exists($filename))){
header("Content-length: ".filesize($filename));
header(‘Content-Type: application/octet-stream‘);
header(‘Content-Disposition: attachment; filename="‘ . $filename . ‘"‘);
readfile("$filename");
} else {
echo "Looks like file does not exist!";
}
}
download(‘/down/test_45f73e852.zip‘);
9、php字符串的截取 限制长度后用‘...‘显示
/*
Utf-8、gb2312都支持的汉字截取函数
cut_str(字符串, 截取长度, 开始长度, 编码);
编码默认为 utf-8
开始长度默认为 0
*/
function cutStr($string, $sublen, $start = 0, $code = ‘UTF-8‘){
if($code == ‘UTF-8‘){
$pa = "/[x01-x7f]|[xc2-xdf][x80-xbf]|xe0[xa0-xbf][x80-xbf]|[xe1-xef][x80-xbf][x80-xbf]|xf0[x90-xbf][x80-xbf][x80-xbf]|[xf1-xf7][x80-xbf][x80-xbf][x80-xbf]/";
preg_match_all($pa, $string, $t_string);
if(count($t_string[0]) - $start > $sublen) return join(‘‘, array_slice($t_string[0], $start, $sublen))."...";
return join(‘‘, array_slice($t_string[0], $start, $sublen));
}else{
$start = $start*2;
$sublen = $sublen*2;
$strlen = strlen($string);
$tmpstr = ‘‘;
for($i=0; $i<$strlen; $i++){
if($i>=$start && $i<($start+$sublen)){
if(ord(substr($string, $i, 1))>129){
$tmpstr.= substr($string, $i, 2);
}else{
$tmpstr.= substr($string, $i, 1);
}
}
if(ord(substr($string, $i, 1))>129) $i++;
}
if(strlen($tmpstr)<$strlen ) $tmpstr.= "...";
return $tmpstr;
}
}
$str = "jQuery插件实现的加载图片和页面效果";
echo cutStr($str,16);
10、PHP获取客户端真实IP
//获取用户真实IP
function getIp() {
if (getenv("HTTP_CLIENT_IP") && strcasecmp(getenv("HTTP_CLIENT_IP"), "unknown"))
$ip = getenv("HTTP_CLIENT_IP");
else
if (getenv("HTTP_X_FORWARDED_FOR") && strcasecmp(getenv("HTTP_X_FORWARDED_FOR"), "unknown"))
$ip = getenv("HTTP_X_FORWARDED_FOR");
else
if (getenv("REMOTE_ADDR") && strcasecmp(getenv("REMOTE_ADDR"), "unknown"))
$ip = getenv("REMOTE_ADDR");
else
if (isset ($_SERVER[‘REMOTE_ADDR‘]) && $_SERVER[‘REMOTE_ADDR‘] && strcasecmp($_SERVER[‘REMOTE_ADDR‘], "unknown"))
$ip = $_SERVER[‘REMOTE_ADDR‘];
else
$ip = "unknown";
return ($ip);
}
echo getIp();
11、随机颜色生成器
function rabdowColor(){
$rand = array(‘0‘, ‘1‘, ‘2‘, ‘3‘, ‘4‘, ‘5‘, ‘6‘, ‘7‘, ‘8‘, ‘9‘, ‘a‘, ‘b‘, ‘c‘, ‘d‘, ‘e‘, ‘f‘);
$color = ‘#‘.$rand[rand(0,15)].$rand[rand(0,15)].$rand[rand(0,15)].$rand[rand(0,15)].$rand[rand(0,15)].$rand[rand(0,15)];
return $color;
}
//$color =rabdowColor();
12、二维数组去重函数
function unique($data = array()){
$tmp = array();
foreach($data as $key => $value){
//把一维数组键值与键名组合
foreach($value as $key1 => $value1){
$value[$key1] = $key1 . ‘_|_‘ . $value1;//_|_分隔符复杂点以免冲突
}
$tmp[$key] = implode(‘,|,‘, $value);//,|,分隔符复杂点以免冲突
}
//对降维后的数组去重复处理
$tmp = array_unique($tmp);
//重组二维数组
$newArr = array();
foreach($tmp as $k => $tmp_v){
$tmp_v2 = explode(‘,|,‘, $tmp_v);
foreach($tmp_v2 as $k2 => $v2){
$v2 = explode(‘_|_‘, $v2);
$tmp_v3[$v2[0]] = $v2[1];
}
$newArr[$k] = $tmp_v3;
}
return $newArr;
}
$newArr = unique($list);
13、截取两个字符之间的内容
function strCutByStr(&$str, $findStart, $findEnd = false, $encoding = ‘utf-8‘){
if(is_array($findStart)){
if(count($findStart) === count($findEnd)){
foreach($findStart as $k => $v){
if(($result = strCutByStr($str, $v, $findEnd[$k], $encoding)) !== false){
return $result;
}
}
return false;
}else{
return false;
}
}
if(($start = mb_strpos($str, $findStart, 0, $encoding)) === false){
return false;
}
$start += mb_strlen($findStart, $encoding);
if($findEnd === false){
return mb_substr($str, $start, NULL, $encoding);
}
if(($length = mb_strpos($str, $findEnd, $start, $encoding)) === false){
return false;
}
return mb_substr($str, $start, $length - $start, $encoding);
}
$str = ‘1那是一场23我问问4567890维稳‘;
echo (strCutByStr($str, ‘那是‘, ‘稳‘));//输出 一场23我问问4567890维
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