php168_cms中提取的验证码

  <?php function yzImg($nmsg){ if (function_exists('imagecreatetruecolor')){ $imstr[0]["s"]=$nmsg[0]; $imstr[1]["s"]=$nmsg[1]; $imstr[2]["s"]=$nmsg[2]; $imstr[3]["s"]=$nmsg[3]; //文件头... header("Content-type: image/png"); //创建真彩色白纸 $im = @imagecreatetruecolor(50, 20) or die("建立图像失败"); //获取背景颜色 $background_color = imagecolorallocate($im, 255, 255, 255); //填充背景颜色(这个东西类似油桶) imagefill($im,0,0,$background_color); //获取边框颜色 $border_color = imagecolorallocate($im,200,200,200); //画矩形，边框颜色200,200,200 imagerectangle($im,0,0,49,19,$border_color); //逐行炫耀背景，全屏用1或0 for($i=2;$i<28;$i++){ //获取随机淡色 $line_color = imagecolorallocate($im,rand(180,255),rand(180,255),rand(180,255)); //画线 imageline($im,2,$i,47,$i,$line_color); } //设置字体大小 $font_size=12; //设置印上去的文字 $Str[0] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"; $Str[1] = "abcdefghijklmnopqrstuvwxyz"; $Str[2] = "01234567891234567890123456"; //获取第1个随机文字 //$imstr[0]["s"] = $Str[rand(0,2)][rand(0,25)]; $imstr[0]["x"] = rand(2,5); $imstr[0]["y"] = rand(1,4); //获取第2个随机文字 //$imstr[1]["s"] = $Str[rand(0,2)][rand(0,25)]; $imstr[1]["x"] = $imstr[0]["x"]+$font_size-1+rand(0,1); $imstr[1]["y"] = rand(1,3); //获取第3个随机文字 //$imstr[2]["s"] = $Str[rand(0,2)][rand(0,25)]; $imstr[2]["x"] = $imstr[1]["x"]+$font_size-1+rand(0,1); $imstr[2]["y"] = rand(1,4); //获取第4个随机文字 //$imstr[3]["s"] = $Str[rand(0,2)][rand(0,25)]; $imstr[3]["x"] = $imstr[2]["x"]+$font_size-1+rand(0,1); $imstr[3]["y"] = rand(1,3); //写入随机字串 for($i=0;$i<4;$i++){ //获取随机较深颜色 $text_color = imagecolorallocate($im,rand(80,180),rand(80,180),rand(80,180)); //画文字 imagechar($im,$font_size,$imstr[$i]["x"],$imstr[$i]["y"],$imstr[$i]["s"],$text_color); } //显示图片 imagepng($im); //销毁图片 imagedestroy($im); exit; } else { header("Pragma:no-cache"); header("Cache-control:no-cache"); header("ContentType: Image/BMP"); $Color[0] = chr(0).chr(0).chr(0); $Color[1] = chr(255).chr(255).chr(255); $_Num[0] = "1110000111110111101111011110111101001011110100101111010010111101001011110111101111011110111110000111"; $_Num[1] = "1111011111110001111111110111111111011111111101111111110111111111011111111101111111110111111100000111"; $_Num[2] = "1110000111110111101111011110111111111011111111011111111011111111011111111011111111011110111100000011"; $_Num[3] = "1110000111110111101111011110111111110111111100111111111101111111111011110111101111011110111110000111"; $_Num[4] = "1111101111111110111111110011111110101111110110111111011011111100000011111110111111111011111111000011"; $_Num[5] = "1100000011110111111111011111111101000111110011101111111110111111111011110111101111011110111110000111"; $_Num[6] = "1111000111111011101111011111111101111111110100011111001110111101111011110111101111011110111110000111"; $_Num[7] = "1100000011110111011111011101111111101111111110111111110111111111011111111101111111110111111111011111"; $_Num[8] = "1110000111110111101111011110111101111011111000011111101101111101111011110111101111011110111110000111"; $_Num[9] = "1110001111110111011111011110111101111011110111001111100010111111111011111111101111011101111110001111"; echo chr(66).chr(77).chr(230).chr(4).chr(0).chr(0).chr(0).chr(0).chr(0).chr(0).chr(54).chr(0).chr(0).chr(0).chr(40).chr(0).chr(0).chr(0).chr(40).chr(0).chr(0).chr(0).chr(10).chr(0).chr(0).chr(0).chr(1).chr(0); echo chr(24).chr(0).chr(0).chr(0).chr(0).chr(0).chr(176).chr(4).chr(0).chr(0).chr(18).chr(11).chr(0).chr(0).chr(18).chr(11).chr(0).chr(0).chr(0).chr(0).chr(0).chr(0).chr(0).chr(0).chr(0).chr(0); for ($i=9;$i>=0;$i--){ for ($j=0;$j<=3;$j++){ for ($k=1;$k<=10;$k++){ echo $Color[substr($_Num[$nmsg[$j]], $i * 10 + $k, 1)]; } } } exit; } } $string_yzimg=yzImgNumRand(4); yzImg($string_yzimg); function yzImgNumRand($lenth){ mt_srand((double)microtime() * 1000000); for($i=0;$i<$lenth;$i++){ $randval.= mt_rand(1,9); } return $randval; } /*==隐逸鸟==*/ ?>

这个生成的验证码只是单纯的数字，背景填充很简单了只是26根直线填充的。前边看到他是想要4为随机字母加数字的序列，可是后来生成序列的时候却仅仅用了数字，字母却并没有用。下面重新修改为4位字母加数字的序列：
 
function yzImgNumRand($lenth){
 mt_srand((double)microtime() * 1000000);
$Str[0] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
 $Str[1] = "abcdefghijklmnopqrstuvwxyz";
 $Str[2] = "01234567891234567890123456";
for($i=0;$i<$lenth;$i++){
  $randval.= $Str[rand(0,2)][rand(0,25)];
}
 return $randval;
}