PHP常用函数推荐

1.产生随机字符串函数
function random($length) { $hash = ''; $chars = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789abcdefghijklmnopqrstuvwxyz'; $max = strlen($chars) - 1; mt_srand((double)microtime() * 1000000); for($i = 0; $i < $length; $i++) { $hash .= $chars[mt_rand(0, $max)]; } return $hash;}2.截取一定长度的字符串
注：该函数对GB2312使用有效
function wordscut($string, $length ,$sss=0) { if(strlen($string) > $length) { if($sss){ $length=$length - 3; $addstr=' ...'; } for($i = 0; $i < $length; $i++) { if(ord($string[$i]) > 127) { $wordscut .= $string[$i].$string[$i + 1]; $i++; } else { $wordscut .= $string[$i]; } } return $wordscut.$addstr; } return $string;}3.取得客户端IP地址
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);}#p#
4.创建相应的文件夹
function createdir($dir=''){ if (!is_dir($dir)) { $temp = explode('/',$dir); $cur_dir = ''; for($i=0;$i5.判断邮箱地址
function checkEmail($inAddress){ return (ereg("^([a-zA-Z0-9_-])+@([a-zA-Z0-9_-])+(.[a-zA-Z0-9_-])+",$inAddress));}6.跳转
function gotourl($message='',$url='',$title="'){ $html ="＜html＞＜head＞"; if(!empty($url)) $html .="＜meta http-equiv='refresh' content="3;url='".$url."'"＞"; $html .="＜link href='../templates/style.css' type=text/css rel=stylesheet＞"; $html .="＜/head＞＜body＞＜br＞＜br＞＜br＞＜br＞"; $html .="＜table cellspacing='0' cellpadding='0' border='1' width='450' align='center'＞"; $html .="＜tr＞＜td bgcolor='#ffffff'＞"; $html .="＜table border='1' cellspacing='1' cellpadding='4' width='100%'＞"; $html .="＜tr class='m_title'＞"; $html .="＜td＞".$title."＜/td＞＜/tr＞"; $html .="＜tr class='line_1'＞＜td align='center' height='60'＞"; $html .="＜br＞".$message."＜br＞＜br＞"; if (!empty($url)) $html .="系统将在3秒后返回＜br＞如果您的浏览器不能自动返回,请点击[＜a href=".$url." target=_self＞这里＜/a＞]进入"; else $html .="[＜a href='#' onclick='history.go(-1)'＞返回＜/a＞]"; $html .="＜/td＞＜/tr＞＜/table＞＜/td＞＜/tr＞＜/table＞"; $html .="＜/body＞＜/html＞"; echo $html; exit;}7.分页（两个函数配合使用）
$totalpage = ceil($sums/$page_size); if((!$page)||($page＜1)) $page=1; $startpos = ($page-1)*$page_size; $sql .=" limit $startpos,$page_size "; return $sql; }function showbar($string=""){ global $page,$totalpage; $out="共＜font color='red'＞＜b＞".$totalpage."＜/b＞＜/font＞页 "; $linkNum =4; $start = ($page-round($linkNum/2))＞0 ? ($page-round($linkNum/2)) : "1"; $end = ($page+round($linkNum/2))＜$totalpage ? ($page+round($linkNum/2)) : $totalpage; $prestart=$start-1; $nextend=$end+1; if($page＜＞1) $out .= "＜a href='?page=1&&".$string."'title=第一页＞第一页＜/a＞ "; if($start＞1) $out.="＜a href='?page=".$prestart."' title=＞..＜＜＜/a＞ "; for($t=$start;$t＜=$end;$t++) { $out .= ($page==$t) ? "＜font color='red'＞＜b＞[".$t."]＜/b＞＜/font＞ " : "＜a href='?page=$t&&".$string."'＞$t＜/a＞ "; } if($end＜$totalpage) $out.="＜a href='?page=".$nextend."&&".$string."' title=＞＞＞..＜/a＞"; if($page＜＞$totalpage) $out .= " ＜a href='?page=".$totalpage."&&".$string."' title=最后页＞最后页＜/a＞"; return $out;}?＞