PHP generates snowflake background verification code program code_PHP tutorial

This article will introduce to you the program code for generating snowflake background verification code in PHP. Friends in need can enter it for reference.

Verification code generation program

The code is as follows

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代码如下

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session_start(); session_register("login_check_number"); //昨晚看到了chianren上的验证码效果，就考虑了一下，用PHP的GD库完成了类似功能 //先成生背景，再把生成的验证码放上去 $img_height=120; //先定义图片的长、宽 $img_width=40; if($HTTP_GET_VARS["act"]== "init"){ //srand(microtime() * 100000);//PHP420后，srand不是必须的 for($Tmpa=0;$Tmpa<4;$Tmpa++){ $nmsg.=dechex(rand(0,15)); }//by sports98 $HTTP_SESSION_VARS[login_check_number] = $nmsg; //$HTTP_SESSION_VARS[login_check_number] = strval(mt_rand("1111","9999")); //生成4位的随机数，放入session中 //谁能做下补充，可以同时生成字母和数字啊？？----由sports98完成了 $aimg = imageCreate($img_height,$img_width); //生成图片 ImageColorAllocate($aimg, 255,255,255); //图片底色，ImageColorAllocate第1次定义颜色PHP就认为是底色了 $black = ImageColorAllocate($aimg, 0,0,0); //定义需要的黑色 ImageRectangle($aimg,0,0,$img_height-1,$img_width-1,$black);//先成一黑色的矩形把图片包围 //下面该生成雪花背景了，其实就是在图片上生成一些符号 for ($i=1; $i<=100; $i++) { //先用100个做测试 imageString($aimg,1,mt_rand(1,$img_height),mt_rand(1,$img_width),"*",imageColorAllocate($aimg,mt_rand(200,255),mt_rand(200,255),mt_rand(200,255))); //哈，看到了吧，其实也不是雪花，就是生成＊号而已。为了使它们看起来"杂乱无章、5颜6色"，就得在1个1个生成它们的时候，让它们的位置、颜色，甚至大小都用随机数，rand()或mt_rand都可以完成。 } //上面生成了背景，现在就该把已经生成的随机数放上来了。道理和上面差不多，随机数1个1个地放，同时让他们的位置、大小、颜色都用成随机数~~ //为了区别于背景，这里的颜色不超过200，上面的不小于200 for ($i=0;$i imageString($aimg, mt_rand(3,5),$i*$img_height/4+mt_rand(1,10),mt_rand(1,$img_width/2), $HTTP_SESSION_VARS[login_check_number][$i],imageColorAllocate($aimg,mt_rand(0,100),mt_rand(0,150),mt_rand(0,200))); } Header("Content-type: image/png"); //告诉浏览器，下面的数据是图片，而不要按文字显示 ImagePng($aimg); //生成png格式。 ImageDestroy($aimg); } ?>

session_start();
session_register("login_check_number");
//I saw the verification code effect on chianren last night, so I thought about it and used PHP’s GD library to complete a similar function
//Generate the background first, then put the generated verification code
$img_height=120; //First define the length and width of the image
$img_width=40;
if($HTTP_GET_VARS["act"]== "init"){
//srand(microtime() * 100000);//After PHP420, srand is not necessary
for($Tmpa=0;$Tmpa<4;$Tmpa++){
           $nmsg.=dechex(rand(0,15));
}//by sports98<🎜> <🎜>
$HTTP_SESSION_VARS[login_check_number] = $nmsg;<🎜> <🎜> //$HTTP_SESSION_VARS[login_check_number] = strval(mt_rand("1111","9999")); //Generate a 4-digit random number and put it into the session
//Who can add something that can generate letters and numbers at the same time? ? ----Complete by sports98<🎜> <🎜> $aimg = imageCreate($img_height,$img_width); //Generate image
ImageColorAllocate($aimg, 255,255,255); //The background color of the picture, the first time ImageColorAllocate defines the color, PHP considers it as the background color
$black = ImageColorAllocate($aimg, 0,0,0); //Define the required black
ImageRectangle($aimg,0,0,$img_height-1,$img_width-1,$black);//First create a black rectangle to surround the image<🎜> <🎜> //It’s time to generate the snowflake background, which is actually to generate some symbols on the picture
for ($i=1; $i<=100; $i++) { //Test with 100 first
imageString($aimg,1,mt_rand(1,$img_height),mt_rand(1,$img_width),"*",imageColorAllocate($aimg,mt_rand(200,255),mt_rand(200,255),mt_rand(200,255))); < br />                     //Ha, you see, it’s not actually a snowflake, it’s just an * sign. In order to make them look "messy and colorful", you have to use random numbers for their position, color, and even size when generating them one by one. This can be done with rand() or mt_rand.
}<🎜> <🎜> //The background is generated above, now it’s time to put the generated random numbers. The principle is similar to the above. Random numbers are placed one by one, and their positions, sizes, and colors are all random numbers~~
//In order to distinguish it from the background, the color here should not exceed 200, and the color above should not be less than 200
for ($i=0;$i imageString($aimg, mt_rand(3,5),$i*$img_height/4+mt_rand(1,10),mt_rand(1,$img_width/2), $HTTP_SESSION_VARS[login_check_number][$i],imageColorAllocate($ aimg,mt_rand(0,100),mt_rand(0,150),mt_rand(0,200)));
}  
Header("Content-type: image/png"); //Tell the browser that the following data is an image instead of text
ImagePng($aimg); //Generate png format.
ImageDestroy($aimg);
}
?>

Verification test page

The code is as follows

代码如下	复制代码
//检验校验码 if(isset($HTTP_POST_VARS["sub"])): if($HTTP_POST_VARS["number"] != $HTTP_SESSION_VARS[login_check_number] || empty($HTTP_POST_VARS["number"])){ echo "校验码不正确!" ; }else{ echo"验证码通过！"; } endif; show_source('test.php'); //以上本页的源码 //以下是生成验证码的源码 show_source('YanZhengMa.php'); ?>

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//Check the check code
if(isset($HTTP_POST_VARS["sub"])):
if($HTTP_POST_VARS["number"] != $HTTP_SESSION_VARS[login_check_number] || empty($HTTP_POST_VARS["number"])){
echo "The check code is incorrect!" ;
}else{
echo "Verification code passed!";
}
endif;
show_source('test.php');
//Source code of the above page

//The following is the source code for generating verification code
show_source('YanZhengMa.php');
?>

http://www.bkjia.com/PHPjc/632956.htmlwww.bkjia.com

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TechArticleThis article will introduce to you the program code for generating snowflake background verification code in PHP. Friends in need can enter it for reference. Verification code generation program code is as follows Copy code ?php session_star...