收藏PHP常用函数收集

<?
function GetIP() { //获取IP
if ($_SERVER["HTTP_X_FORWARDED_FOR"])
$ip = $_SERVER["HTTP_X_FORWARDED_FOR"];
else if ($_SERVER["HTTP_CLIENT_IP"])
$ip = $_SERVER["HTTP_CLIENT_IP"];
else if ($_SERVER["REMOTE_ADDR"])
$ip = $_SERVER["REMOTE_ADDR"];
else if (getenv("HTTP_X_FORWARDED_FOR"))
$ip = getenv("HTTP_X_FORWARDED_FOR");
else if (getenv("HTTP_CLIENT_IP"))
$ip = getenv("HTTP_CLIENT_IP");
else if (getenv("REMOTE_ADDR"))
$ip = getenv("REMOTE_ADDR");
else
$ip = "Unknown";
return $ip;
}
?>
<?php
function DateAdd($date, $int, $unit = "d") { //时间的增加（还可以改进成时分秒都可以增加，有时间再补上）
$dateArr = explode("-", $date);
$value[$unit] = $int; //开源代码OSPhP.COm.CN
return date("Y-m-d", mktime(0,0,0, $dateArr[1] + $value['m'], $dateArr[2] + $value['d'], $dateArr[0] + $value['y']));
}
function GetWeekDay($date) { //计算出给出的日期是星期几
$dateArr = explode("-", $date);
return date("w", mktime(0,0,0,$dateArr[1],$dateArr[2],$dateArr[0]));
}
?>
<?
function check_date($date) { //检查日期是否合法日期
$dateArr = explode("-", $date);
if (is_numeric($dateArr[0]) && is_numeric($dateArr[1]) && is_numeric($dateArr[2])) {
return checkdate($dateArr[1],$dateArr[2],$dateArr[0]);
}
return false;
}
function check_time($time) { //检查时间是否合法时间
$timeArr = explode(":", $time);
if (is_numeric($timeArr[0]) && is_numeric($timeArr[1]) && is_numeric($timeArr[2])) {
if (($timeArr[0] >= 0 && $timeArr[0] <= 23) && ($timeArr[1] >= 0 && $timeArr[1] <= 59) && ($timeArr[2] >= 0 && $timeArr[2] <= 59)) //OSPHP.com.CN
return true;
else
return false;
}
return false;
}
function DateDiff($date1, $date2, $unit