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Some commonly used functions_PHP tutorial
- WBOYOriginal
- 2016-07-20 10:59:51849browse
These are some functions that are used frequently, some of which come from other people’s programs...
1. Generate random string function
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 $hash;
}
2. Intercept a string of a certain length
Note: This function is valid for GB2312
function wordscut($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. Obtain the client IP address
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");