Experience Sharing summary common PHP Functions

Common PHP functions 1. generate random string functions

1. Function random ($ length ){
2. $ Hash = @#@#;
3. $ Chars =@# abcdefghijklmnopqrstuvwxyz0123456789abcdefghijklmnopqrstuvwxyz @#;
4. $ Max = strlen ($ chars)-1;
5. Mt_srand (double) microtime () * 1000000 );
6. For ($ I = 0; $ I <$ length; $ I ++ ){
7. $ Hash. = $ chars [mt_rand (0, $ max)];
8. }
9. Return $ hash;
10. }

Common PHP functions 2. intercepting strings 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;  
  
  
}  
 
 

Common PHP functions 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");  
  
  
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);  
  
  
}  
 
 

Common PHP functions 4. Create corresponding folders
 

 
 

  
  
function createdir($dir=@#@#)  
  
  
{  
  
  
if (!is_dir($dir))  
  
  
{  
  
  
$temp = explode(@#/@#,$dir);  
  
  
$cur_dir = @#@#;  
  
  
for($i=0;$i<count($temp);$i++)  
  
  
{  
  
  
$cur_dir .= $temp[$i].@#/@#;  
  
  
if (!is_dir($cur_dir))  
  
  
{  
  
  
@mkdir($cur_dir,0777);  
  
  
}  
  
  
}