PHP简单的图片验证码实现

//第一段代码生成随机图片------code2.php

1. //开启session以用于保存生成的内容
2. session_start();
3. $table=array(
4. "pic0"=>"dog",
5. "pic1"=>"cat",
6. "pic2"=>"fish",
7. "pic3"=>"bird"
8. );
9. $index=rand(0,3);
10. $value=$table['pic'.$index];
11. $_SESSION['authcode']=$value;
12. //得到随机生成的图片名
13. $filename=dirname(__FILE__).'/pic'.$index.'.jpg';
14. $content=file_get_contents($filename);
15. header('Content-type:image/jpg');
16. echo $content;
17. ?>

//第二段代码实线表单的验证

1. if(isset($_REQUEST['authcode'])){
2. session_start();
3. if($_REQUEST['authcode']==$_SESSION['authcode']){
4. echo "right";
5. }else{
6. echo "sad story
   ";
7. echo $_REQUEST['authcode'];
8. }
9. }
10. ?>
20. ?>

/*代码的路径是linux的路径*/