您的位置:

php完整验证码实例(php完整验证码实例怎么用)

本文目录一览:

求一个php验证码及如何使用的例子?

以前项目中的东西

在没有GB库的情况下也可以生成验证码

关键部分做出了注释

img src="image.php"

?php

//存为文件 image.php

error_reporting(E_ALL ^ E_NOTICE);

require_once('image.class.php');

$image_model = new Image();

//可以在此处更改属性达到验证码不同大小的图片

$image_model-outputBrowser();

?

?php

/*

* \验证码生成类 存为文件image.class.php

* \如果不支持GD库,则采用像素画法

* \详见

*/

class Image

{

var $img_height = 20; //图片的长

var $img_width = 68; //图片的宽

var $img_cache = ''; //图像信息缓存

var $check_number = ''; //验证码

var $lenght = 4; //验证码位数

var $is_gd = false;

//'----------以下为不支持GD需要的变量

var $pixels = '';

var $digits = '';

var $lines = '';

var $data = '';

var $chunk = '';

var $crc_table = '';

function Image()

{

session_start();

session_register("check_number");

$this-session = $_SESSION;

$this-is_gd = function_exists('gd_info') ? true : false;

$this-getCheckNumber();

if( $this-is_gd ):

$this-getFromGD();

else:

$this-getFromCode();

endif;

}

//'----浏览器输出

function outputBrowser()

{

if( $this-is_gd )

{

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($this-img_cache); //生成png格式。。。嘿嘿效果蛮像回事的嘛。。。

ImageDestroy($this-img_cache);

}

else echo($this-img_cache);

}

//'----文件输出

function outputFile($filename=null)

{

if(!$filename)$filename=time().'.png';

$fp = fopen($filename, 'w+');

fwrite($fp, $this-img_cache);

fclose($fp);

}

//'----得到验证码

function getCheckNumber()

{

//srand(microtime() * 100000);//PHP420后,srand不是必须的

for($Tmpa=0;$Tmpa$this-lenght;$Tmpa++)

{

$this-check_number.= $this-is_gd ? dechex(rand(0,15)) : rand(0,3);

}

unset($Tmpa);

$this-session['check_number'] = strtoupper($this-check_number);

}

//'----用GD库生成

function getFromGD()

{

//$black = '';

$this-img_cache = imageCreate($this-img_width,$this-img_height); //生成图片

//图片底色,ImageColorAllocate第1次定义颜色PHP就认为是底色了

$black = ImageColorAllocate($this-img_cache, 255,255,255);

//下面该生成雪花背景了,其实就是在图片上生成一些符号

//先用100个做测试

/*

for ($i=1; $i=15; $i++)

{

imageString($this-img_cache,1,mt_rand(1,$this-img_height-10),mt_rand(1,$this-img_width-10),".",

imageColorAllocate($this-img_cache,mt_rand(100,255),mt_rand(0,250),mt_rand(0,200)));

//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

imagettftext($this-img_cache, 20, 0, 10, 20, $black, "./html/VINERITC.TTF", "AC67");

for ($i=0;$istrlen($this-session['check_number']);$i++)

{

imagettftext($this-img_cache, 14, rand(0,30), $i*$this-img_width/4 + 3, 17, imageColorAllocate($this-img_cache,mt_rand(0,100),mt_rand(0,150),mt_rand(0,200)), "./html/VINERITC.TTF", $this-session['check_number'][$i]);

}

for($i=0;$i100;$i++)//加入干扰象素

{

imagesetpixel($this-img_cache, rand()%70 , rand()%30 , imageColorAllocate($this-img_cache,mt_rand(100,255),mt_rand(0,250),mt_rand(0,200)));

}

$black = ImageColorAllocate($this-img_cache, 0,0,0); //定义需要的黑色

//先成一黑色的矩形把图片包围

ImageRectangle($this-img_cache,0,0, $this-img_width-1,$this-img_height-1, $black);

}

//End Function getGD

#-----------------------------------------------------------------------------------------------------------------------

function set_4pixel($r, $g, $b, $x, $y)

{

$ofs = 3 * ($this-img_width * $y + $x);

$this-pixels[$ofs] = chr($r);

$this-pixels[$ofs + 1] = chr($g);

$this-pixels[$ofs + 2] = chr($b);

$this-pixels[$ofs + 3] = chr($r);

$this-pixels[$ofs + 4] = chr($g);

$this-pixels[$ofs + 5] = chr($b);

$ofs += 3 * $this-img_width;

$this-pixels[$ofs] = chr($r);

$this-pixels[$ofs + 1] = chr($g);

$this-pixels[$ofs + 2] = chr($b);

$this-pixels[$ofs + 3] = chr($r);

$this-pixels[$ofs + 4] = chr($g);

$this-pixels[$ofs + 5] = chr($b);

}

//生成数字图象的函数

function draw2digits($x, $y, $number)

{

//$this-draw_digit($x, $y, intval($number / 10) );

$this-draw_digit($x + 11, $y, $number % 10);

}

function draw_digit($x, $y, $digit)

{

$digit = $this-digits[$digit];

$m = 8;

for($b = 1, $i = 0; $i 7; $i++, $b *= 2)

{

if(($b $digit) == $b)

{

$j = $i * 4;

$x0 = $this-lines[$j] * $m + $x;

$y0 = $this-lines[$j + 1] * $m + $y;

$x1 = $this-lines[$j + 2] * $m + $x;

$y1 = $this-lines[$j + 3] * $m + $y;

if($x0 == $x1)

{

$ofs = 3 * ($this-img_width * $y0 + $x0);

for($h = $y0; $h = $y1; $h++, $ofs += 3 * $this-img_width)

{

$this-pixels[$ofs] = chr(0);

$this-pixels[$ofs + 1] = chr(0);

$this-pixels[$ofs + 2] = chr(0);

}

}

else

{

$ofs = 3 * ($this-img_width * $y0 + $x0);

for($w = $x0; $w = $x1; $w++)

{

$this-pixels[$ofs++] = chr(0);

$this-pixels[$ofs++] = chr(0);

$this-pixels[$ofs++] = chr(0);

}

}

}//End if

}//End for

}

//将文字加入到图象中

function add_chunk($type)

{

// chunk :为层

// length: 4 字节: 用来计算 chunk

// chunk type: 4 字节

// chunk data: length bytes

// CRC: 4 字节: 循环冗余码校验

// copy data and create CRC checksum

$len = strlen($this-data);

$this-chunk = pack("c*", ($len 24) 255,

($len 16) 255,

($len 8) 255,

$len 255);

$this-chunk .= $type;

$this-chunk .= $this-data;

//calculate a CRC checksum with the bytes chunk[4..len-1]

$z = 16777215;

$z |= 255 24;

$c = $z;

for ($n = 4; $n strlen($this-chunk); $n++) {

$c8 = ($c 8) 0xffffff;

$c = $this-crc_table[($c ^ ord($this-chunk[$n])) 0xff] ^ $c8;

}

$crc = $c ^ $z;

$this-chunk .= chr(($crc 24) 255);

$this-chunk .= chr(($crc 16) 255);

$this-chunk .= chr(($crc 8) 255);

$this-chunk .= chr($crc 255);

//将结果加到$img_cache中

$this-img_cache .= $this-chunk;

}

//主程序

function getFromCode()

{

//填充

for($h = 0; $h $this-img_height; $h++)

{

for($w = 0; $w $this-img_width; $w++)

{

$r = 100 / $this-img_width * $w + 155;

$g = 100 / $this-img_height * $h + 155;

$b = 255 - (100 / ($this-img_width + $this-img_height) * ($w + $h));

$this-pixels .= chr($r);

$this-pixels .= chr($g);

$this-pixels .= chr($b);

}

}

$this-digits = array(95, 5, 118, 117, 45, 121, 123, 69, 127, 125);

$this-lines = array(1, 1, 1, 2, 0, 1, 0, 2, 1, 0, 1, 1, 0, 0, 0, 1, 0, 2, 1, 2, 0, 1, 1, 1, 0, 0, 1, 0);

for($i=0; $i$this-lenght; $i++)

{

$this-draw2digits($i*13, 2, $this-check_number[$i]);

}

//$this-set_4pixel(0, 0, 0, 26, 7);

//$this-set_4pixel(0, 0, 0, 26, 13);

//$this-set_4pixel(0, 0, 0, 52, 7);

//$this-set_4pixel(0, 0, 0, 52, 13);

//创建循环冗余码校验表

$z = -306674912;// = 0xedb88320

for ($n = 0; $n 256; $n++)

{

$c = $n;

for ($k = 0; $k 8; $k++)

{

$c2 = ($c 1) 0x7fffffff;

if($c 1) $c = $z ^ ($c2);

else $c = $c2;

}

$this-crc_table[$n] = $c;

}

// PNG file signature

$this-img_cache = pack("c*", 137,80,78,71,13,10,26,10);

// IHDR chunk data:

// width: 4 bytes

// height: 4 bytes

// bit depth: 1 byte (8 bits per RGB value)

// color type: 1 byte (2 = RGB)

// compression method: 1 byte (0 = deflate/inflate)

// filter method: 1 byte (0 = adaptive filtering)

// interlace method: 1 byte (0 = no interlace)

$this-data = pack("c*", ($this-img_width24) 255,

($this-img_width 16) 255,

($this-img_width 8) 255,

$this-img_width 255,

($this-img_height 24) 255,

($this-img_height 16) 255,

($this-img_height 8) 255,

$this-img_height 255, 8, 2, 0, 0, 0);

$this-add_chunk("IHDR");

//以下不敢乱翻译,请自行参考

// scanline:

// filter byte: 0 = none

// RGB bytes for the line

// the scanline is compressed with "zlib", method 8 (RFC-1950):

// compression method/flags code: 1 byte ($78 = method 8, 32k window)

// additional flags/check bits: 1 byte ($01: FCHECK = 1, FDICT = 0, FLEVEL = 0)

// compressed data blocks: n bytes

// one block (RFC-1951):

// bit 0: BFINAL: 1 for the last block

// bit 1 and 2: BTYPE: 0 for no compression

// next 2 bytes: LEN (LSB first)

// next 2 bytes: one's complement of LEN

// LEN bytes uncompressed data

// check value: 4 bytes (Adler-32 checksum of the uncompressed data)

$len = ($this-img_width * 3 + 1) * $this-img_height;

$this-data = pack("c*", 0x78, 0x01, 1, $len 255, ($len8) 255, 255 - ($len 255), 255 - (($len 8) 255) );

$start = strlen($this-data);

$i2 = 0;

for($h = 0; $h $this-img_height; $h++)

{

$this-data .= chr(0);

for($w = 0; $w $this-img_width * 3; $w++)

{

$this-data .= $this-pixels[$i2++];

}

}

//calculate a Adler32 checksum with the bytes data[start..len-1]

$s1 = 1;

$s2 = 0;

for ($n = $start; $n strlen($this-data); $n++)

{

$s1 = ($s1 + ord($this-data[$n])) % 65521;

$s2 = ($s2 + $s1) % 65521;

}

$adler = ($s2 16) | $s1;

$this-data .= chr(($adler 24) 255);

$this-data .= chr(($adler 16) 255);

$this-data .= chr(($adler 8) 255);

$this-data .= chr($adler 255);

$this-add_chunk("IDAT");

//IEND: marks the end of the PNG-file

$this-data = "";

$this-add_chunk("IEND");

//列印图象

//echo($this-img_cache);

}

}//End Class

?

怎么用PHP写个验证码

首先,当用户打开页面时随机产生一个session,然后根据这个值生成验证码图片。

第二,将验证码图片显示到表单上。

第三,当用户提交时表单时,比较session里的值与表单中验证码的值进行比较。

简单的实现过程:

复杂的验证码图片生成:

php验证码怎么实现

1. 新建code.php验证码生成文件

在此之前必须打开php的GD库,修改php.ini文件的配置,取消extension=php_gd2.dll前面的分号。代码如下:

?php

session_start();

//生成验证码图片

Header("Content-type: image/PNG");

$im = imagecreate(44,18);

$back = ImageColorAllocate($im, 245,245,245);

imagefill($im,0,0,$back); //背景

srand((double)microtime()*1000000);

//生成4位数字

for($i=0;$i4;$i++){

$font = ImageColorAllocate($im, rand(100,255),rand(0,100),rand(100,255));

$authnum=rand(1,9);

$vcodes.=$authnum;

imagestring($im, 5, 2+$i*10, 1, $authnum, $font);

}

for($i=0;$i100;$i++) //加入干扰象素

{

$randcolor = ImageColorallocate($im,rand(0,255),rand(0,255),rand(0,255));

imagesetpixel($im, rand()p , rand()0 , $randcolor);

}

ImagePNG($im);

ImageDestroy($im);

$_SESSION['Checknum'] = $vcodes;

?

2. 显示验证码图片

在需要显示验证码的页面中加入

input type="text" name="passcode"

img src="code.php"

3.判断并获取验证码的值

验证码是通过第一步骤代码中的$_SESSION['Checknum'] = $vcodes;赋的值,所以验证码的值存在$_SESSION['Checknum']当中。在验证页面,使用以下代码,

...

session_start();//启动会话

$code=$_POST["passcode"];

if( $code == $_SESSION["Checknum"])

{...}即可完成验证码登录。

运行截图:

望采纳,谢谢