php生成验证码的函数,实用靠谱。先上下生成的验证码的效果图(这里生成的是全数字的验证码的示例效果):
下面是php生成验证码的源码:
<?php session_start(); //session_register('CheckCode'); //PHP4.2以上版本不需要用session_register()注册SESSION变量 $type='gif'; $width= 45; $height= 20; header("Content-type: image/".$type); srand((double)microtime()*1000000); if(isset($_GET['action'])){ $randval=randStr(4,$_GET['action']); }else{ $randval=randStr(4,''); } if($type!='gif'&&function_exists('imagecreatetruecolor')){ $im=@imagecreatetruecolor($width,$height); }else{ $im=@imagecreate($width,$height); } $r=Array(225,211,255,223); $g=Array(225,236,237,215); $b=Array(225,236,166,125); $key=rand(0,3); $backColor=ImageColorAllocate($im,$r[$key],$g[$key],$b[$key]);//背景色(随机) $borderColor=ImageColorAllocate($im,127,157,185);//边框色 $pointColor=ImageColorAllocate($im,255,170,255);//点颜色 @imagefilledrectangle($im,0,0,$width - 1,$height - 1,$backColor);//背景位置 @imagerectangle($im,0,0,$width-1,$height-1,$borderColor); //边框位置 $stringColor=ImageColorAllocate($im,255,51,153); for($i=0;$i<=100;$i++){ $pointX=rand(2,$width-2); $pointY=rand(2,$height-2); @imagesetpixel($im,$pointX,$pointY,$pointColor); } @imagestring($im,5,5,1,$randval,$stringColor); $ImageFun='Image'.$type; $ImageFun($im); @imagedestroy($im); $_SESSION['CheckCode']=$randval; function randStr($len=6,$format='ALL'){ switch($format){ case 'ALL'://生成包含数字和字母的验证码 $chars='ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789'; break; case 'CHAR'://仅生成包含字母的验证码 $chars='ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz'; break; case 'NUMBER'://仅生成包含数字的验证码 $chars='0123456789'; break; default : $chars='ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789'; break; } $string=''; while(strlen($string)<$len) $string.=substr($chars,(mt_rand()%strlen($chars)),1); return $string; }
该函数的具体使用方法请看如下这个示例(这里是生成全数字的验证码):
<img src="/static/imghwm/default1.png" data-src="checkCode.php?action=NUMBER" class="lazy" style="max-width:90%" style="max-width:90%" / alt="php生成验证码函数_PHP" >
以上就是php如何生成验证码的实现函数,希望对大家的学习有所帮助。

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PHP and Python have their own advantages and disadvantages, and the choice depends on project needs and personal preferences. 1.PHP is suitable for rapid development and maintenance of large-scale web applications. 2. Python dominates the field of data science and machine learning.

PHP is widely used in e-commerce, content management systems and API development. 1) E-commerce: used for shopping cart function and payment processing. 2) Content management system: used for dynamic content generation and user management. 3) API development: used for RESTful API development and API security. Through performance optimization and best practices, the efficiency and maintainability of PHP applications are improved.

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PHP and Python each have their own advantages, and choose according to project requirements. 1.PHP is suitable for web development, especially for rapid development and maintenance of websites. 2. Python is suitable for data science, machine learning and artificial intelligence, with concise syntax and suitable for beginners.

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