本文实例为大家分享了PHP验证码类，利用对象来实现的验证码类，供大家参考，具体内容如下

<?php

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Class Image{

 private $img;

 public $width = 85;

 public $height = 25;

 public $code;

 public $code_len = 4;

 public $code_str = "329832983DSDSKDSLKQWEWQ2lkfDSFSDjfdsfdsjwlkfj93290KFDSKJFDSOIDSLK";

 public $bg_color = '#DCDCDC';

 public $font_size = 16;

 public $font = 'font.ttf';

 public $font_color = '#000000';

 //创建验证码饿字符创

 public function create_code(){

  $code = '';

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

   $code .= $this->code_str[mt_rand(0, strlen($this->code_str)-1)];

 }

  return $this->code = $code;

 }

 //输出图像

 public function getImage(){

  $w = $this->width;

  $h = $this->height;

  $bg_color = $this->bg_color;

  $img = imagecreatetruecolor($w, $h);

  $bg_color = imagecolorallocate($img, 

 hexdec(substr($bg_color, 1,2)), hexdec(substr($bg_color, 3,2)), hexdec(substr($bg_color, 5,2)));

 imagefill($img, 0, 0, $bg_color);

  $this->img = $img;

  $this->create_font();

  $this->create_pix();

 $this->show_code();

 }

 //写入验证码

 public function create_font(){

  $this->create_code();

  $color = $this->font_color;

  $font_color = imagecolorallocate($this->img, hexdec(substr($color,1,2)), hexdec(substr($color, 3,2)), hexdec(substr($color,5,2)));

  $x = $this->width/$this->code_len;

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

   $txt_color = imagecolorallocate($this->img, mt_rand(0,100), mt_rand(0, 150), mt_rand(0, 200));

   imagettftext($this->img, $this->font_size, mt_rand(-30, 30), $x*$i+mt_rand(3, 6), mt_rand($this->height/1.2, $this->height), $txt_color, $this->font , $this->code[$i]); 

   //imagestring($this->img, $this->font_size, $x*$i+mt_rand(3, 6),mt_rand(0, $this->height/4) , $this->code[$i], $font_color);

  }

  $this->font_color = $font_color;

 }

 //画干扰线

 public function create_pix(){

  $pix_color= $this->font_color;

  for($i=0;$i<100;$i++){

   imagesetpixel($this->img, mt_rand(0, $this->width),mt_rand(0, $this->height), $pix_color);

  }

  for($j=0;$j<4;$j++){

   imagesetthickness($this->img, mt_rand(1, 2));

   imageline($this->img, mt_rand(0, $this->width), mt_rand(0, $this->height), mt_rand(0, $this->width), mt_rand(0, $this->height), $pix_color);

  }

 }

 //得到验证码

 public function getCode(){

  return strtoupper($this->code);

 }

 //输出验证码

 private function show_code(){

  header("Content-type:image/png");

  imagepng($this->img);

  imagedestroy($this->img);

 }

}

以上就是使用对象编写的验证码类的全部内容，希望对大家学习PHP程序设计有所帮助。