


PHP Chinese alphanumeric verification code class, customizable font_PHP tutorial
In actual project development, verification code problems are often encountered, such as login pages, message pages, registration pages...
The principle of the verification code is very simple: use the GD library to create an image. Of course, the image must be added with the necessary interference code, and then save the SESSION on the server side. When the user submits, it will be judged whether the sessions are the same.
The PHP verification code class shared today supports Chinese characters, alphanumerics, and can also customize font files, which is enough for everyone to use
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* Captcha Class base on PHP GD Lib
* @author Design
* @version 1.0
* @copyright js8.in 2010
* @demo
* include('captchaClass.php');
* $captchaDemo=new Captcha();
* $captchaDemo->createImage();
*/
class Captcha{
//@Define the height of the verification code image
private $height;
//@Define the width of the verification code image
private $width;
//@Define the number of characters in the verification code
private $textNum;
//@Define the verification code character content
private $textContent;
//@Define the character color
private $fontColor;
//@Define the random text color
private $randFontColor;
//@Define font size
private $fontSize;
//@Define font
private $fontFamily;
//@Define background color
private $bgColor;
//@Define the random background color
private $randBgColor;
//@Define the character language
private $textLang;
//@Define the number of interference points
private $noisePoint;
//@Define the number of interference lines
private $noiseLine;
//@Define whether to distort
private $distortion;
//@Define the distorted image source
private $distortionImage;
//@Define whether there is a border
private $showBorder;
//@Define the verification code image source
private $image;
//@ Constructor constructor
public function Captcha(){
$this->textNum=4;
$this->fontSize=16;
$this->fontFamily='c:\ windows\fontsSIMYOU.ttf';//Set Chinese fonts, you can change it to the Linux directory
$this->textLang='en';
$this->noisePoint=30;
$this ->noiseLine=3;
$this->distortion=false;
$this->showBorder=false;
} // from bkjia.com
//@ Set the image width
public function setWidth($w){
$this->width=$w;
}
//@Set the image height
public function setHeight( $h){
$this->height=$h;
}
//@Set the number of characters
public function setTextNumber($textN){
$this ->textNum=$textN;
}
//@Set character color
public function setFontColor($fc){
$this->fontColor=sscanf($fc, '#%2x%2x%2x');
}
//@Set font size
public function setFontSize($n){
$this->fontSize=$n;
}
//@Set font
public function setFontFamily($ffUrl){
$this->fontFamily=$ffUrl;
}
/ /@Set character language
public function setTextLang($lang){
$this->textLang=$lang;
}
//@Set image background
public function setBgColor($bc){
$this->bgColor=sscanf($bc,'#%2x%2x%2x');
}
//@Set the number of interference points
public function setNoisePoint($n){
$this->noisePoint=$n;
}
//@Set the number of interference lines
public function setNoiseLine($n) {
$this->noiseLine=$n;
}
//@Set whether to distort
public function setDistortion($b){
$this->distortion =$b;
}
//@Set whether to display the border
public function setShowBorder($border){
$this->showBorder=$border;
}
//@Initialization verification code image
public function initImage(){
if(empty($this->width)){$this->width=floor($this-> ;fontSize*1.3)*$this->textNum+10;}
if(empty($this->height)){$this->height=$this->fontSize*2;}
$this->image=imagecreatetruecolor($this->width,$this->height);
if(empty($this->bgColor)){
$this-> randBgColor=imagecolorallocate($this->image,mt_rand(100,255),mt_rand(100,255),mt_rand(100,255));
}else{
$this->randBgColor=imagecolorallocate($this-> image,$this->bgColor[0],$this->bgColor[1],$this->bgColor[2]);
}
imagefill($this->image,0 ,0,$this->randBgColor);
}
//@Generate random characters
public function randText($type){
$string='';
switch($type){
case 'en':
$str='ABCDEFGHJKLMNPQRSTUVWXY3456789';
for($i=0;$itextNum;$i++){
$string=$string.','.$str[mt_rand(0,29)];
}
break;
case 'cn':
for($i=0;$ itextNum;$i++) {
$string=$string.','.chr(rand(0xB0,0xCC)).chr(rand(0xA1,0xBB));
}
$string=iconv('GB2312','UTF-8',$string); //Convert encoding to utf8
break;
}
return substr($string,1);
}
//@输出文字到验证码
public function createText(){
$textArray=explode(',',$this->randText($this->textLang));
$this->textContent=join('',$textArray);
if(empty($this->fontColor)){
$this->randFontColor=imagecolorallocate($this->image,mt_rand(0,100),mt_rand(0,100),mt_rand(0,100));
}else{
$this->randFontColor=imagecolorallocate($this->image,$this->fontColor[0],$this->fontColor[1],$this->fontColor[2]);
}
for($i=0;$itextNum;$i++){
$angle=mt_rand(-1,1)*mt_rand(1,20);
imagettftext($this->image,$this->fontSize,$angle,5+$i*floor($this->fontSize*1.3),floor($this->height*0.75),$this->randFontColor,$this->fontFamily,$textArray[$i]);
}
}
//@生成干扰点
public function createNoisePoint(){
for($i=0;$inoisePoint;$i++){
$pointColor=imagecolorallocate($this->image,mt_rand(0,255),mt_rand(0,255),mt_rand(0,255));
imagesetpixel($this->image,mt_rand(0,$this->width),mt_rand(0,$this->height),$pointColor);
}
}
//@产生干扰线
public function createNoiseLine(){
for($i=0;$inoiseLine;$i++) {
$lineColor=imagecolorallocate($this->image,mt_rand(0,255),mt_rand(0,255),20);
imageline($this->image,0,mt_rand(0,$this->width),$this->width,mt_rand(0,$this->height),$lineColor);
}
}
//@扭曲文字
public function distortionText(){
$this->distortionImage=imagecreatetruecolor($this->width,$this->height);
imagefill($this->distortionImage,0,0,$this->randBgColor);
for($x=0;$xwidth;$x++){
for($y=0;$yheight;$y++){
$rgbColor=imagecolorat($this->image,$x,$y);
imagesetpixel($this->distortionImage,(int)($x+sin($y/$this->height*2*M_PI-M_PI*0.5)*3),$y,$rgbColor);
}
}
$this->image=$this->distortionImage;
}
//@生成验证码图片
public function createImage(){
$this->initImage(); //创建基本图片
$this->createText(); //输出验证码字符
if($this->distortion){$this->distortionText();} //扭曲文字
$this->createNoisePoint(); //产生干扰点
$this->createNoiseLine(); //产生干扰线
if($this->showBorder){imagerectangle($this->image,0,0,$this->width-1,$this->height-1,$this->randFontColor);} //添加边框
imagepng($this->image);
imagedestroy($this->image);
if($this->distortion){imagedestroy($this->$distortionImage);}
return $this->textContent;
}
}
使用方法:
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header("Content-type:image/png");
include('captcha5_class.php');
$captcha5=new Captcha();
//@设置验证码宽度
//$captcha5->setWidth(200);
//@设置验证码高度
//$captcha5->setHeight(50);
//@设置字符个数
$captcha5->setTextNumber(5);
//@设置字符颜色
//$captcha5->setFontColor('#ff9900');
//@设置字号大小
//$captcha5->setFontSize(25);
//@设置字体
$captcha5->setFontFamily('c:\windows\fonts\STXINGKA.TTF');
//@设置语言
$captcha5->setTextLang('cn');
//@设置背景颜色
//$captcha5->setBgColor('#000000');
//@设置干扰点数量
//$captcha5->setNoisePoint(600);
//@设置干扰线数量
//$captcha5->setNoiseLine(10);
//@设置是否扭曲
//$captcha5->setDistortion(true);
//@设置是否显示边框
$captcha5->setShowBorder(true);
//输出验证码
$code=$captcha5->createImage();
//$_SESSION['captchaCode']['content']=$code;
//$_SESSION['captchaCode']['time']=microtime();
?>

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