还算功能比较全的PHP验证码类_PHP教程_编程技术--HTML5中文学习网

看到PHP100视频34讲写的php验证码类，支持自定义图片大小、字符个数、字符类型、字符大小、图片类型、汉字验证码、干扰线等，注释详细

字体文件是微软雅黑，和验证码文件同目录，文件名msyh.ttf，可以从C:/windows/fonts目录找到，复制到同目录即可

<?php

/**

* @version Id: imgcode.php 2012-11-30 k

* @package imgcode.php

* @Purview default

* @link http://www.3oom.com

$img = new img_code();

$img->show();

class img_code{

private $img_type = 'png';//输出图片类型 png,gif,jpg

private $line = TRUE;//是否增加干扰线

private $text = '2';//验证码类型：0数字，1字母，2汉字

private $text_size= 20;//字体大小

private $length = 4;//字符串长度

private $width = 120;//图片宽度，像素

private $height = 40;//图片高度，像素

private $font_file= 'msyh.ttf';//字体文件

public $img = '';

* 创建图片

private function img_create(){

$this->img = imagecreate($this->width, $this->height);

imagecolorallocate($this->img, 255,255,255);

}

* 显示图片

public function show(){

@session_start();

$this->img_create();

if($this->line){

$this->img_line();

}

$this->img_text();

$this->img_header();

imagedestroy($im);

exit();

}

* 生成字符串

private function img_text(){

$rand_string = '';

$im = &$this->img;

$fontColor[] = imagecolorallocate($im, 0x15, 0x15, 0x15);

$fontColor[] = imagecolorallocate($im, 0x95, 0x1e, 0x04);

$fontColor[] = imagecolorallocate($im, 0x93, 0x14, 0xa9);

$fontColor[] = imagecolorallocate($im, 0x12, 0x81, 0x0a);

$fontColor[] = imagecolorallocate($im, 0x06, 0x3a, 0xd5);

if($this->text<2){

//数字，字母

for($i=0;$i<$this->length;$i++){

if($this->text){

$c=chr(mt_rand(65,90));

}else{

$c=chr(mt_rand(48,57));

}

if( $c=='I' ) $c = 'K';

if( $c=='O' ) $c = 'E';

$rand_string[]=$c;

}

}else{

//汉字,此处可以引入汉字文件

$arr=array('大','小','多','少','人','天','水','土','木','火','云');

for($i=0;$i<$this->length;$i++){

$l = count($arr)-1;

//文件编码为gbk需要转换

//$rand_string[] = iconv('gb2312','utf-8',$arr[mt_rand(0,$l)]);

$rand_string[] = $arr[mt_rand(0,$l)];

}

$_SESSION['imgcode']=$rand_string;

$_c = count($rand_string);

for($i=0;$i<$_c;$i++)

{

if($this->text == 1){

$rand_string[$i] = strtoupper($rand_string[$i]);

}

$c_fontColor = $fontColor[mt_rand(0,4)];

$y = $this->height-($this->height-$this->text_size)/2;

$x = ($this->width-($this->text_size+2)*$this->length)/2;

$y_pos = $i==0 ? $x : $i*($this->text_size+2)+$x;

$c = mt_rand(0, 15);

@imagettftext($im, $this->text_size, $c, $y_pos, $y, $c_fontColor, $this->font_file, $rand_string[$i]);

}

* 生成线条

private function img_line(){

$im = &$this->img;

$img_width = $this->width;

$img_height= $this->height;

//背景横线

$lineColor1 = imagecolorallocate($im, 0xda, 0xd9, 0xd1);

for($j=3; $j<=$img_height-3; $j=$j+3)

{

imageline($im, 2, $j, $img_width - 2, $j, $lineColor1);

}

//背景竖线

$lineColor2 = imagecolorallocate($im, 0xda,0xd9,0xd1);

for($j=2;$j<$img_width-6;$j=$j+6)

{

imageline($im, $j, 0, $j+8, $img_height, $lineColor2);

}

//画边框

if( $use_boder && $filter_type == 0 )

{

$bordercolor = imagecolorallocate($im, 0x9d, 0x9e, 0x96);

imagerectangle($im, 0, 0, $img_width-1, $img_height-1, $bordercolor);

}

* 生成输出

private function img_header(){

header("Pragma:no-cache/r/n");

header("Cache-Control:no-cache/r/n");

header("Expires:0/r/n");

if($this->img_type == 'jpg'){

header('Content-type: image/jpeg');

imagejpeg($this->img);

}else if($this->img_type == 'png'){

header('Content-type: image/png');

imagepng($this->img);

}else{

header('Content-type: image/gif');

imagegif($this->img);

}

文章来源：http://www.3oom.com/blog/50.html