php如何生成验证码代码分享

更新时间：2024-05-07 14:16:46 作者：肥宅-季波我要评论(0)

利用PHP生成验证码需要用到GD2库。GD2库引用方法网络上有很多，不同操作系统导入方式也不同。

<?php
$iC = new idCode(5,60,30);
$iC->createPNG();
class idCode{
private $words = array('a','b',
'c','d','e','f','g','h','i','j','k','l',
'm','n','o','p','q','r','s','t','u','v',
'w','x','y','z','A','B','C','D','E','F',
'G','H','I','J','K','L','M','N','O','P',
'Q','R','S','T','U','V','W','X','Y','Z',
'0','1','2','3','4','5','6','7','8','9');
private $fonts;
private $count;//验证码字符数
private $height;
private $width;
private $path = '..\myfolder\fonts';
private $keys;
//构造函数
public function __construct($count,$width,$height){
$this->count = $count;
$this->getFonts();
$this->height = $height;
$this->width = $width;
}
private function getFonts(){
$dir = dir($this->path);
while(false !== ($file = $dir->read())){
if($file != '.' && $file != '..'){
$this->fonts[count($this->fonts)] = basename($file);
}
}
$dir->close();
}
private function createKeys(){
for($i = 0;$i < $this->count;$i++){
$this->keys[$i]['char'] = $this->words[rand(0,count($this->words)-1)];
//使用字体路径标识
$this->keys[$i]['filename'] = $this->path.'\\'.$this->fonts[rand(0,count($this->fonts)-1)];
}
}
public function createPNG(){
$this->createKeys();
//创建画布以及颜色块儿
$bg = imagecreatetruecolor($this->width + 10*2,$this->height + 3*2);//两边留10px空白,上下3px
$grey = imagecolorallocate($bg,155,155,155);
$blue = imagecolorallocate($bg,0x00,0x00,0xff);
//填充背景
imagefill($bg,0,0,$grey);
//添加字符
$pwidth = $this->width/$this->count;
$x;$y;
for($i = 0;$i < $this->count;$i++){
$rotation = rand(-40,40);//偏转角度±40°
$fontsize = 33;
$width_txt;
$height_txt;
do{
$fontsize--;
$bbox = imagettfbbox($fontsize,$rotation,$this->keys[$i]['filename'],$this->keys[$i]['char']);
$width_txt = $bbox[2] - $bbox[0];//x 0 2 4 6,y1 3 5 7;左下，右下，右上，左上
$height_txt = $bbox[7] - $bbox[1];
}while($fontsize > 8 && ($height_txt > $this->height || $width_txt > $pwidth));
$fontcolor = imagecolorallocate($bg,rand(0,255),rand(0,255),rand(0,255));
$x = 8 + $pwidth*$i + $pwidth/2 - $width_txt/2;//x坐标基本位置
$y = $this->height/2 - $height_txt/2;
imagettftext($bg,$fontsize,$rotation,$x,$y,$fontcolor,$this->keys[$i]['filename'],$this->keys[$i]['char']);
}
//绘制干扰线
//根据字体酌情增加干扰线
imageline($bg,0,15,40,10,$blue);
//图像输出头文件
header('Content-type:image/png');
//输出png图像
imagepng($bg);
//清除缓存资源
imagedestroy($bg);
}
public function checkKeys($input){
if(count($input)!=$this->count){
return 'ERROR:长度不正确.';
}else{
for($i=0;$i < $this->count;$i++){
//0 o O I l 1 校准,根据所选择的字体确定是否需要手动校准
if($input[$i] != $this->keys[$i]['char']){
return 'SUCCESS.';
}else{
return 'ERROR:请输入正确验证码.';
}
}
}
}
}
?>