In-depth discussion on how to improve PHP operating efficiency_PHP Tutorial

As we all know, Improve PHP operating efficiency 1. In a function, when passing an array

using return is more efficient than using global

For example

1. function userloginfo($usertemp){
2. $detail=explode("|",$usertemp);
3. return $detail;
4. } 🎜>
=
5. userloginfo($userdb); Than

function userloginfo($usertemp){

global $detail;
1. $
2. detail
=
3. explode("|",$usertemp); } userloginfo($userdb);
4. Be efficient
5. Improve PHP operating efficiency 2, (this code is used to get the URL corresponding to the program directory, recommended)

This code is more efficient than

<ol class="dp-xml">
<li class="alt"><span><span>$</span><span class="attribute">urlarray</span><span>=</span><span class="attribute-value">explode</span><span>('/',$HTTP_<br>SERVER_VARS['REQUEST_URI']);   </span></span></li>
<li>
<span>$</span><span class="attribute">urlcount</span><span>=count($urlarray);unset<br>($urlarray[$urlcount-1]);   </span>
</li>
<li class="alt">
<span>$</span><span class="attribute">ofstarurl</span><span>=</span><span class="attribute-value">'http://'</span><span>.<br>$HTTP_SERVER_VARS['HTTP_HOST'].<br>implode('/',$urlarray);  </span>
</li>
</ol>

Improve PHP running efficiency 3

,

in the loop When making judgments, it is more efficient to use identity ratio for numerical judgment

<ol class="dp-xml">
<li class="alt"><span><span>$</span><span class="attribute">pre_urlarray</span><span>=</span><span class="attribute-value">explode</span><span>('/',$HTTP_SERVER_VARS['HTTP_REFERER']);   </span></span></li>
<li>
<span>$</span><span class="attribute">pre_url</span><span>=</span><span class="attribute-value">array_pop</span><span>($pre_urlarray); </span>
</li>
</ol>

, such as

<ol class="dp-xml"><li class="alt"><span><span>$</span><span class="attribute">a</span><span>=</span><span class="attribute-value">2</span><span>;$</span><span class="attribute">b</span><span>=</span><span class="attribute-value">2</span><span>;  </span></span></li></ol>

More efficient than

<ol class="dp-xml"><li class="alt"><span><span>if($</span><span class="attribute">a</span><span>==$b)$</span><span class="attribute">c</span><span>=$a;   </span></span></li></ol>

to improve PHP operating efficiency 4,

mysql Try to use where in when querying and use less limit

<ol class="dp-xml"><li class="alt"><span><span>if($</span><span class="attribute">a</span><span>===$b)$</span><span class="attribute">c</span><span>=$a;  </span></span></li></ol>

limit checks the first few records of multiple records, which is very fast, but querying the top few records will be slow.

Use in. When querying continuous records, it is very fast and non-continuous. The first run of the record will be a little slower, but it will be faster after that!

Improve PHP operating efficiency 5,

NT server data operation stability is not as good as unix/linux

Improve PHP operating efficiency 6,

Try to use ob_start() before output; it can speed up the output, suitable for NT or nuli/linux, for unlix servers. Use ob_start('ob_gzhandler'); the output efficiency will be higher

Improve PHP operating efficiency 7,

Try to use if ($a==his value) Try to use if(empty($a)) when negating, because this way the program runs faster

Improving PHP operating efficiency 8,

Use unequal time != is equivalent to < >

Improve PHP operating efficiency 9,

My personal experience is to use $a="11111111111111"; for the efficiency and $a= '11111111111111'; Quite. It is not very different as the book says.

Improve PHP operating efficiency 10,

Using standardized SQL statements will be beneficial to MySQL. Analysis of

Improving PHP operating efficiency 11

,Using

COOKIE will be done immediately To take effect

Use

<ol class="dp-xml">
<li class="alt"><span><span>if($online){   </span></span></li>
<li>
<span>$</span><span class="attribute">online1</span><span>=$online;   </span>
</li>
<li class="alt"><span>setcookie('online1',$online,<br>$cookietime,$ckpath,$ckdomain,$secure);   </span></li>
<li><span>}  </span></li>
</ol>

COOKIE needs to be refreshed again to take effect

Improve PHP operating efficiency 12 ,

<ol class="dp-xml">
<li class="alt"><span><span>if($online)   </span></span></li>
<li><span>setcookie('online1',$online,<br>$cookietime,$ckpath,$ckdomain,$secure);  </span></li>
</ol>

using

is better than

both in terms of speed and stability. Excellent

<ol class="dp-xml">
<li class="alt"><span><span>$</span><span class="attribute">handle</span><span>=</span><span class="attribute-value">fopen</span><span>($filename,wb);   </span></span></li>
<li><span>flock($handle,LOCK_SH);   </span></li>
<li class="alt">
<span>$</span><span class="attribute">filedata</span><span>=</span><span class="attribute-value">fread</span><span>($handle,<br>filesize($filename));   </span>
</li>
<li><span>fclose($handle);  </span></li>
</ol>

Improve PHP operating efficiency 13, truncate string optimization function (can avoid the appearance of ? characters)

<ol class="dp-xml"><li class="alt"><span><span>file($filename);  </span></span></li></ol>

For example,

Improve PHP running efficiency 14, shield case in the program

<ol class="dp-xml">
<li class="alt"><span><span>ifunction substrs($content,$length) {   </span></span></li>
<li>
<span>if(strlen($content)</span><span class="tag">></span><span>$length){   </span>
</li>
<li class="alt">
<span>$</span><span class="attribute">num</span><span>=</span><span class="attribute-value">0</span><span>;   </span>
</li>
<li>
<span>for($</span><span class="attribute">i</span><span>=</span><span class="attribute-value">0</span><span>;$i</span><span class="tag"><</span><span>$length-3;$i++) {   </span></li><li class="alt"><span>if(ord($content[$i])</span><span class="tag">></span><span>127)$num++;   </span>
</li>
<li><span>}   </span></li>
<li class="alt">
<span>$num%</span><span class="attribute">2</span><span>==1 ? $</span><span class="attribute">content</span><span>=</span><span class="attribute-value">substr</span><span>(<br>$content,0,$length-4):$</span><span class="attribute">content<br></span><span>=</span><span class="attribute-value">substr</span><span>($content,0,$length-3);   </span>
</li>
<li>
<span>$</span><span class="attribute">content.</span><span>=</span><span class="attribute-value">' ...'</span><span>;   </span>
</li>
<li class="alt"><span>}   </span></li>
<li><span>return $content;   </span></li>
<li class="alt"><span>}   </span></li>
</ol>

<ol class="dp-xml"><li class="alt"><span><span>$newarray[1]=substrs($newarray[1],25); </span></span></li></ol>

Improve PHP running efficiency Efficiency 15, do not use file(); and do not use fget(); (unstable or slow) Take an array function

<ol class="dp-xml">
<li class="alt"><span><span>for ($</span><span class="attribute">asc</span><span>=</span><span class="attribute-value">65</span><span>;$asc</span><span class="tag"><</span><span>=90;$asc++)   </span></span></li><li><span>{ //strtolower() 此函数在一些服务<br />器会产生乱码!   </span></li><li class="alt"><span>if (strrpos($regname,chr($asc))!==false)   </span></li><li><span>{   </span></li><li class="alt"><span>$</span><span class="attribute">error</span><span>=</span><span class="attribute-value">"为了避免用户名混乱,用户名<br />中禁止使用大写字母，请使用小写字母"</span><span>;   </span></li><li><span>$</span><span class="attribute">reg_check</span><span>=</span><span class="attribute-value">0</span><span>;   </span></li><li class="alt"><span>}   </span></li><li><span>} </span></li></ol>

Although the code of this function is relatively There are many, but it has great advantages in improving PHP operating efficiency in terms of speed and stability!

<ol class="dp-xml"><li class="alt"><span><span>function openfile($filename,$</span><span class="attribute">method</span><span>=</span><span class="attribute-value">"rb"</span><span>)   </span></span></li><li><span>{   </span></li><li class="alt"><span>$</span><span class="attribute">handle</span><span>=@fopen($filename,$method);   </span></li><li><span>@flock($handle,LOCK_SH);   </span></li><li class="alt"><span>@$</span><span class="attribute">filedata</span><span>=</span><span class="attribute-value">fread</span><span>($handle,filesize<br />($filename));   </span></li><li><span>@fclose($handle);   </span></li><li class="alt"><span>$</span><span class="attribute">filedata</span><span>=</span><span class="attribute-value">str_replace</span><span>("n","<br />n</span><span class="tag"><</span><span class="tag-name">ofstar:</span><span class="tag">></span><span>",$filedata);   </span></span></li>
<li>
<span>$</span><span class="attribute">filedb</span><span>=</span><span class="attribute-value">explode</span><span>("</span><span class="tag"><</span><span class="tag-name">ofstar:</span><span class="tag">></span><span>",$filedata);   </span>
</li>
<li class="alt"><span>//array_pop($filedb);   </span></li>
<li>
<span>$</span><span class="attribute">count</span><span class="attribute-value">count</span><span>=count($filedb);   </span>
</li>
<li class="alt"><span>if($filedb[$count-1]==''){unset<br>($filedb[$count-1]);}   </span></li>
<li><span>return $filedb;   </span></li>
<li class="alt"><span>}  </span></li>
</ol>

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TechArticleEveryone knows that to improve PHP operating efficiency 1, in functions, using return when passing arrays is more efficient than using global For example, functionuserloginfo($usertemp){ $ detail = explode (|,$userte...