本文实例总结了一些在php应用开发中常用到的函数，这些函数有字符操作，文件操作及其它的一些操作了，分享给大家供大家参考。具体如下：
<?php
/**
* 获取客户端IP
* @return [string] [description]
*/
function getClientIp() {
$ip = NULL;
if (isset($_SERVER['HTTP_X_FORWARDED_FOR'])) {
$arr = explode(',', $_SERVER['HTTP_X_FORWARDED_FOR']);
$pos = array_search('unknown',$arr);
if(false !== $pos) unset($arr[$pos]);
$ip = trim($arr[0]);
}elseif (isset($_SERVER['HTTP_CLIENT_IP'])) {
$ip = $_SERVER['HTTP_CLIENT_IP'];
}elseif (isset($_SERVER['REMOTE_ADDR'])) {
$ip = $_SERVER['REMOTE_ADDR'];
}
// IP地址合法验证
$ip = (false !== ip2long($ip)) ? $ip : '0.0.0.0';
return $ip;
}
/**
* 获取在线IP
* @return String
*/
function getOnlineIp($format=0) {
global $S_GLOBAL;
if(empty($S_GLOBAL['onlineip'])) {
if(getenv('HTTP_CLIENT_IP') && strcasecmp(getenv('HTTP_CLIENT_IP'), 'unknown')) {
$onlineip = getenv('HTTP_CLIENT_IP');
} elseif(getenv('HTTP_X_FORWARDED_FOR') && strcasecmp(getenv('HTTP_X_FORWARDED_FOR'), 'unknown')) {
$onlineip = getenv('HTTP_X_FORWARDED_FOR');
} elseif(getenv('REMOTE_ADDR') && strcasecmp(getenv('REMOTE_ADDR'), 'unknown')) {
$onlineip = getenv('REMOTE_ADDR');
} elseif(isset($_SERVER['REMOTE_ADDR']) && $_SERVER['REMOTE_ADDR'] && strcasecmp($_SERVER['REMOTE_ADDR'], 'unknown')) {
$onlineip = $_SERVER['REMOTE_ADDR'];
}
preg_match("/[\d\.]{7,15}/", $onlineip, $onlineipmatches);
$S_GLOBAL['onlineip'] = $onlineipmatches[0] ? $onlineipmatches[0] : 'unknown';
}
if($format) {
$ips = explode('.', $S_GLOBAL['onlineip']);
for($i=0;$i<3;$i++) {
$ips[$i] = intval($ips[$i]);
}
return sprintf('%03d%03d%03d', $ips[0], $ips[1], $ips[2]);
} else {
return $S_GLOBAL['onlineip'];
}
}
/**
* 获取url
* @return [type] [description]
*/
function getUrl(){
$pageURL = 'http';
if (isset($_SERVER["HTTPS"]) && $_SERVER["HTTPS"] == "on") {
$pageURL .= "s";
}
$pageURL .= "://";
if ($_SERVER["SERVER_PORT"] != "80") {
$pageURL .= $_SERVER["HTTP_HOST"] . ":" . $_SERVER["SERVER_PORT"] . $_SERVER["REQUEST_URI"];
} else {
$pageURL .= $_SERVER["HTTP_HOST"] . $_SERVER["REQUEST_URI"];
}
return $pageURL;
}
/**
* 获取当前站点的访问路径根目录
* @return [type] [description]
*/
function getSiteUrl() {
$uri = $_SERVER['REQUEST_URI']?$_SERVER['REQUEST_URI']:($_SERVER['PHP_SELF']?$_SERVER['PHP_SELF']:$_SERVER['SCRIPT_NAME']);
return 'http://'.$_SERVER['HTTP_HOST'].substr($uri, 0, strrpos($uri, '/')+1);
}
/**
* 字符串截取，支持中文和其他编码
* @param [string] $str [字符串]
* @param integer $start [起始位置]
* @param integer $length [截取长度]
* @param string $charset [字符串编码]
* @param boolean $suffix [是否有省略号]
* @return [type] [description]
*/
function msubstr($str, $start=0, $length=15, $charset="utf-8", $suffix=true) {
if(function_exists("mb_substr")) {
return mb_substr($str, $start, $length, $charset);
} elseif(function_exists('iconv_substr')) {
return iconv_substr($str,$start,$length,$charset);
}
$re['utf-8'] = "/[\x01-\x7f]|[\xc2-\xdf][\x80-\xbf]|[\xe0-\xef][\x80-\xbf]{2}|[\xf0-\xff][\x80-\xbf]{3}/";
$re['gb2312'] = "/[\x01-\x7f]|[\xb0-\xf7][\xa0-\xfe]/";
$re['gbk'] = "/[\x01-\x7f]|[\x81-\xfe][\x40-\xfe]/";
$re['big5'] = "/[\x01-\x7f]|[\x81-\xfe]([\x40-\x7e]|\xa1-\xfe])/";
preg_match_all($re[$charset], $str, $match);
$slice = join("",array_slice($match[0], $start, $length));
if($suffix) {
return $slice."…";
}
return $slice;
}
/**
* php 实现js escape 函数
* @param [type] $string [description]
* @param string $encoding [description]
* @return [type] [description]
*/
function escape($string, $encoding = 'UTF-8'){
$return = null;
for ($x = 0; $x < mb_strlen($string, $encoding);$x ++)
{
$str = mb_substr($string, $x, 1, $encoding);
if (strlen($str) > 1) { // 多字节字符
$return .= "%u" . strtoupper(bin2hex(mb_convert_encoding($str, 'UCS-2', $encoding)));
} else {
$return .= "%" . strtoupper(bin2hex($str));
}
}
return $return;
}
/**
* php 实现 js unescape函数
* @param [type] $str [description]
* @return [type] [description]
*/
function unescape($str) {
$str = rawurldecode($str);
preg_match_all("/(?:%u.{4})|.{4};|&#\d+;|.+/U",$str,$r);
$ar = $r[0];
foreach($ar as $k=>$v) {
if(substr($v,0,2) == "%u"){
$ar[$k] = iconv("UCS-2","utf-8//IGNORE",pack("H4",substr($v,-4)));
} elseif(substr($v,0,3) == "") {
$ar[$k] = iconv("UCS-2","utf-8",pack("H4",substr($v,3,-1)));
} elseif(substr($v,0,2) == "&#") {
echo substr($v,2,-1)."";
$ar[$k] = iconv("UCS-2","utf-8",pack("n",substr($v,2,-1)));
}
}
return join("",$ar);
}
/**
* 数字转人名币
* @param [type] $num [description]
* @return [type] [description]
*/
function num2rmb ($num) {
$c1 = "零壹贰叁肆伍陆柒捌玖";
$c2 = "分角元拾佰仟万拾佰仟亿";
$num = round($num, 2);
$num = $num * 100;
if (strlen($num) > 10) {
return "oh,sorry,the number is too long!";
}
$i = 0;
$c = "";
while (1) {
if ($i == 0) {
$n = substr($num, strlen($num)-1, 1);
} else {
$n = $num % 10;
}
$p1 = substr($c1, 3 * $n, 3);
$p2 = substr($c2, 3 * $i, 3);
if ($n != '0' || ($n == '0' && ($p2 == '亿' || $p2 == '万' || $p2 == '元'))) {
$c = $p1 . $p2 . $c;
} else {
$c = $p1 . $c;
}
$i = $i + 1;
$num = $num / 10;
$num = (int)$num;
if ($num == 0) {
break;
}
}
$j = 0;
$slen = strlen($c);
while ($j < $slen) {
$m = substr($c, $j, 6);
if ($m == '零元' || $m == '零万' || $m == '零亿' || $m == '零零') {
$left = substr($c, 0, $j);
$right = substr($c, $j + 3);
$c = $left . $right;
$j = $j-3;
$slen = $slen-3;
}
$j = $j + 3;
}
if (substr($c, strlen($c)-3, 3) == '零') {
$c = substr($c, 0, strlen($c)-3);
} // if there is a '0' on the end , chop it out
return $c . "整";
}
/**
* 特殊的字符
* @param [type] $str [description]
* @return [type] [description]
*/
function makeSemiangle($str) {
$arr = array(
'０' => '0', '１' => '1', '２' => '2', '３' => '3', '４' => '4',
'５' => '5', '６' => '6', '７' => '7', '８' => '8', '９' => '9',
'Ａ' => 'A', 'Ｂ' => 'B', 'Ｃ' => 'C', 'Ｄ' => 'D', 'Ｅ' => 'E',
'Ｆ' => 'F', 'Ｇ' => 'G', 'Ｈ' => 'H', 'Ｉ' => 'I', 'Ｊ' => 'J',
'Ｋ' => 'K', 'Ｌ' => 'L', 'Ｍ' => 'M', 'Ｎ' => 'N', 'Ｏ' => 'O',
'Ｐ' => 'P', 'Ｑ' => 'Q', 'Ｒ' => 'R', 'Ｓ' => 'S', 'Ｔ' => 'T',
'Ｕ' => 'U', 'Ｖ' => 'V', 'Ｗ' => 'W', 'Ｘ' => 'X', 'Ｙ' => 'Y',
'Ｚ' => 'Z', 'ａ' => 'a', 'ｂ' => 'b', 'ｃ' => 'c', 'ｄ' => 'd',
'ｅ' => 'e', 'ｆ' => 'f', 'ｇ' => 'g', 'ｈ' => 'h', 'ｉ' => 'i',
'ｊ' => 'j', 'ｋ' => 'k', 'ｌ' => 'l', 'ｍ' => 'm', 'ｎ' => 'n',
'ｏ' => 'o', 'ｐ' => 'p', 'ｑ' => 'q', 'ｒ' => 'r', 'ｓ' => 's',
'ｔ' => 't', 'ｕ' => 'u', 'ｖ' => 'v', 'ｗ' => 'w', 'ｘ' => 'x',
'ｙ' => 'y', 'ｚ' => 'z',
'（' => '(', '）' => ')', '〔' => '[', '〕' => ']', '【' => '[',
'】' => ']', '〖' => '[', '〗' => ']', '｛' => '{', '｝' => '}', '《' => '<',
'》' => '>',
'％' => '%', '＋' => '+', '—' => '-', '－' => '-', '～' => '-',
'：' => ':', '。' => '.', '、' => ',', '，' => '.', '、' => '.',
'；' => ';', '？' => '?', '！' => '!', '…' => '-', '‖' => '|',
'”' => '"', '“' => '"', ''' => '`', '‘' => '`', '｜' => '|', '〃' => '"',
' ' => ' ','．' => '.');
return strtr($str, $arr);
}
/**
* 下载
* @param [type] $filename [description]
* @param string $dir [description]
* @return [type] [description]
*/
function downloads($filename,$dir='./'){
$filepath = $dir.$filename;
if (!file_exists($filepath)){
header("Content-type: text/html; charset=utf-8");
echo "File not found!";
exit;
} else {
$file = fopen($filepath,"r");
Header("Content-type: application/octet-stream");
Header("Accept-Ranges: bytes");
Header("Accept-Length: ".filesize($filepath));
Header("Content-Disposition: attachment; filename=".$filename);
echo fread($file, filesize($filepath));
fclose($file);
}
}
/**
* 创建一个目录树
* @param [type] $dir [description]
* @param integer $mode [description]
* @return [type] [description]
*/
function mkdirs($dir, $mode = 0777) {
if (!is_dir($dir)) {
mkdirs(dirname($dir), $mode);
return mkdir($dir, $mode);
}
return true;
}以上就是(实用篇)非常实用的PHP常用函数汇总的内容，更多相关内容请关注PHP中文网（www.php.cn）！
