Experience Sharing Summary of Common PHP Functions_PHP Tutorial

PHP common functions 1. Generate random string function

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. }

Commonly used functions in PHP 2. Intercept a string of a certain length

Note: This function is valid for gb2312

<ol class="dp-xml"><li class="alt"><span><span>function wordscut($string, $length ,$</span><span class="attribute">sss</span><span>=</span><span class="attribute-value">0</span><span>) {  </span></span></li><li><span>if(strlen($string) </span><span class="tag">></span><span> $length) {  </span>
</li>
<li class="alt"><span>if($sss){  </span></li>
<li>
<span>$</span><span class="attribute">length</span><span>=$length - 3;  </span>
</li>
<li class="alt">
<span>$</span><span class="attribute">addstr</span><span>=@# ...@#;  </span>
</li>
<li><span>}  </span></li>
<li class="alt">
<span>for($</span><span class="attribute">i</span><span> = </span><span class="attribute-value">0</span><span>; $i </span><span class="tag"><</span><span> $length; $i++) {  </span></li><li><span>if(ord($string[$i]) </span><span class="tag">></span><span> 127) {  </span>
</li>
<li class="alt">
<span>$wordscut </span><span class="attribute">.</span><span>= $string[$i].$string[$i + 1];  </span>
</li>
<li><span>$i++;  </span></li>
<li class="alt"><span>} else {  </span></li>
<li>
<span>$wordscut </span><span class="attribute">.</span><span>= $string[$i];  </span>
</li>
<li class="alt"><span>}  </span></li>
<li><span>}  </span></li>
<li class="alt"><span>return $wordscut.$addstr;  </span></li>
<li><span>}  </span></li>
<li class="alt"><span>return $string;  </span></li>
<li><span>}  </span></li>
</ol>
<p><strong>Commonly used in PHP Function 3. Get the client ip address </strong><br> </p>
<pre class="brush:php;toolbar:false"><ol class="dp-xml">
<li class="alt"><span><span>function getip(){  </span></span></li>
<li><span>if (getenv("http_client_ip") <br>&& strcasecmp(getenv("http_client_ip"), "unknown"))  </span></li>
<li class="alt">
<span>$</span><span class="attribute">ip</span><span> = </span><span class="attribute-value">getenv</span><span>("http_client_ip");  </span>
</li>
<li><span>else if (getenv("http_x_forwarded_for") <br>&& strcasecmp(getenv("http_x_forwarded_for"), "unknown"))  </span></li>
<li class="alt">
<span>$</span><span class="attribute">ip</span><span> = </span><span class="attribute-value">getenv</span><span>("http_x_forwarded_for");  </span>
</li>
<li><span>else if (getenv("remote_addr")<br> && strcasecmp(getenv("remote_addr"), "unknown"))  </span></li>
<li class="alt">
<span>$</span><span class="attribute">ip</span><span> = </span><span class="attribute-value">getenv</span><span>("remote_addr");  </span>
</li>
<li><span>else if (isset($_server[@#remote_addr@#])<br> && $_server[@#remote_addr@#] <br>&& strcasecmp($_server[@#remote_addr@#], "unknown"))  </span></li>
<li class="alt">
<span>$</span><span class="attribute">ip</span><span> = $_server[@#remote_addr@#];  </span>
</li>
<li><span>else  </span></li>
<li class="alt">
<span>$</span><span class="attribute">ip</span><span> = </span><span class="attribute-value">"unknown"</span><span>;  </span>
</li>
<li><span>return($ip);  </span></li>
<li class="alt"><span>}  </span></li>
</ol>

PHP common functions 4. Create the corresponding folder

<ol class="dp-xml">
<li class="alt"><span><span>function createdir($</span><span class="attribute">dir</span><span>=@#@#)  </span></span></li>
<li><span>{  </span></li>
<li class="alt"><span>if (!is_dir($dir))  </span></li>
<li><span>{  </span></li>
<li class="alt">
<span>$</span><span class="attribute">temp</span><span> = </span><span class="attribute-value">explode</span><span>(@#/@#,$dir);  </span>
</li>
<li>
<span>$</span><span class="attribute">cur_dir</span><span> = @#@#;  </span>
</li>
<li class="alt">
<span>for($</span><span class="attribute">i</span><span>=</span><span class="attribute-value">0</span><span>;$i</span><span class="tag"><</span><span class="tag-name">count</span><span>($temp);$i++)  </span>
</li>
<li><span>{  </span></li>
<li class="alt">
<span>$cur_dir </span><span class="attribute">.</span><span>= $temp[$i].@#/@#;  </span>
</li>
<li><span>if (!is_dir($cur_dir))  </span></li>
<li class="alt"><span>{  </span></li>
<li><span>@mkdir($cur_dir,0777);  </span></li>
<li class="alt"><span>}  </span></li>
<li><span>}  </span></li>
</ol>

http://www.bkjia.com/PHPjc/446157.htmlwww.bkjia.comtruehttp: //www.bkjia.com/PHPjc/446157.htmlTechArticlePHP common functions 1. Generate random string function functionrandom($length){ $ hash =@#@#; $ chars =@#abcdefghijklmnopqrstuvwxyz0123456789abcdefghijklmnopqrstuvwxyz@#; $ max = strlen ($ch...