一个简单的php验证码程序
本文章介绍一下关于在php中验证码程序的生成代码,调用方法及以如果验证用户输入的验证码程序没有问题.
create_code.php,代码如下:
- <?php
- session_start();
-
- header("Content-type: image/png");
-
- $str = "1,2,3,4,5,6,7,8,9,a,b,c,d,f,g";
- $list = explode(",", $str);
- $cmax = count($list) - 1;
- $verifyCode = '';
- for ( $i=0; $i < 5; $i++ ){
- $randnum = mt_rand(0, $cmax);
- $verifyCode .= $list[$randnum];
- }
- $_SESSION['code'] = $verifyCode;
-
- $im = imagecreate(58,28);
- $black = imagecolorallocate($im, 0,0,0);
- $white = imagecolorallocate($im, 255,255,255);
- $gray = imagecolorallocate($im, 200,200,200);
- $red = imagecolorallocate($im, 255, 0, 0);
- imagefill($im,0,0,$white);
-
-
- imagestring($im, 5, 10, 8, $verifyCode, $black);
-
- for($i=0;$i<50;$i++)
- {
- imagesetpixel($im, rand()p , rand()0 , $black);
- imagesetpixel($im, rand()p , rand()0 , $red);
- imagesetpixel($im, rand()p , rand()0 , $gray);
-
-
- }
- imagepng($im);
- imagedestroy($im);
- ?>
html代码,demo.html代码如下:
-
- <html xmlns="http://www.w3.org/1999/xhtml">
- <head>
- <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
- <title></title>
- </head>
-
- <body>
- <form action="act.php" method="post">
- <input type="text" name="code" />
- <img id="code" src="create_code.php" alt="看不清楚,换一张" style="cursor: pointer; vertical-align:middle;" onClick="create_code()"/>
-
- <button type="submit">提交</button>
- </form>
- <script>
- function create_code(){
- document.getElementByIdx_x('code').src = 'create_code.php?'+Math.random()*10000;
- }
- </script>
- </body>
- </html>
处理,判断是否输入正确 act.php,代码如下:
- <?php
- session_start();
- if($_POST['code'] == $_SESSION['code']){
- echo 'ok';
- }else{
- echo 'no';
- }
- ?>