1. In a function, when passing an array, using return is more efficient than using global. For example,
function userloginfo($usertemp){
$detail=explode("|",$usertemp);
return $detail;
}
$ login=userloginfo($userdb);
Better than
function userloginfo($usertemp){
global $detail;
$detail=explode("|",$usertemp);
}
userloginfo($userdb);
Be efficient
2, (This code is used to get the URL corresponding to the program directory, recommended)
$urlarray=explode('/',$HTTP_SERVER_VARS['REQUEST_URI']);
$urlcount=count($urlarray);unset($urlarray [$urlcount-1]);
$ofstarurl='http://'.$HTTP_SERVER_VARS['HTTP_HOST'].implode('/',$urlarray);
This code is better than
$pre_urlarray=explode('/ ',$HTTP_SERVER_VARS['HTTP_REFERER']);
$pre_url=array_pop($pre_urlarray);
Be efficient
3. When judging in a loop, use the identity ratio for numerical judgment to be efficient
$a=2;$b =2;
For example
if($a==$b)$c=$a;
than
if($a===$b)$c=$a;
efficient
4, try to use mysql when querying Where in, use limit less.
limit is very fast to check the first few records of multiple records, but it will be slow to query the top few records.
Use in. When querying continuous records, it is very fast. When running non-continuous records, it will be very fast for the first time. A little slower, but it will be faster in the future!
5. The stability of NT server data operation is not as good as unix/linux
6. Try to use ob_start() before output; it can speed up the output speed, suitable for NT or nuli/linux, and for unlix classes If the server uses ob_start('ob_gzhandler'); the output efficiency will be higher
7. When judging, try to use if ($a==its value). When negative, try to use if (empty($a)), because this program Runs faster
8. When using unequal time!=, the efficiency is equivalent to <>.
9. Personal experience is that the efficiency of using $a="11111111111111"; is equivalent to $a='11111111111111';. It is not like what the book says. There is a big difference
10. Using standardized SQL statements will be beneficial to MySQL parsing
11. Use
if($online){
$
setcookie('online1',$online,$cookietime,$ckpath,$ckdomain ,$secure);
}
COOKIE will take effect immediately
Use
if($online)
setcookie('online1',$online,$cookietime,$ckpath,$ckdomain,$secure);
COOKIE needs to be refreshed again Effective
12, use
$handle=fopen($filename,wb);
flock($handle,LOCK_SH);
$filedata=fread($handle,filesize($filename));
fclose($handle);
Than
file($filename);
Excellent in both speed and stability
13, truncation string optimization function (can avoid the appearance of ? characters)
function substrs($content,$length) {
if(strlen($ content)>$length){
$num=0;
for($i=0;$i<$length-3;$i++) {
if(ord($content[$i])>127) $num++;
}
$num%2==1 ? $c
$content.=' ...';
}
return $content;
}
For example, $newarray[1]=substrs($newarray[1 ],25);
14, case shielding in the program
for ($asc=65;$asc<=90;$asc++)
{ //strtolower() This function will produce garbled characters on some servers!
if (strrpos ($regname,chr($asc))!==false)
{
$error="In order to avoid confusion in usernames, uppercase letters are prohibited in usernames, please use lowercase letters";
$reg_check=0;
}
}
15, do not use file(); and do not use fget(); (unstable or slow) Take an array function
function openfile($filename,$method="rb")
{
$handle=@ fopen($filename,$method);
@flock($handle,LOCK_SH);
@$filedata=fread($handle,filesize($filename));
@fclose($handle);
$filedata=str_replace( "n","n
$filedb=explode("
//array_pop($filedb);
$count=count ($filedb);
if($filedb[$count-1]==''){unset($filedb[$count-1]);}
return $filedb;
}
//Although the code of this function is relatively small A lot, but it has great advantages in speed and stability!
The above has introduced the hd audio bus driver PHP running efficiency summary and program speed, including the content of the hd audio bus driver. I hope it will be helpful to friends who are interested in PHP tutorials.