php-验证码
<html> <body> <h2>用户注册：</h2> <br> <form action="a.php" method="post"> 账 号：<input type="text" name="zh" id=""> <br> 密 码：<input type="password" name="mm" id=""> <br> 验证码：<input type="text"name="yzm"> <br> <img src="yzm.php"> <br> <input type="submit" value="提交"> <input type="reset" value="重置"> </form> </body> </html>
//html页面
<?php $a = imagecreatetruecolor(100,20); //画布 $black = imagecolorallocate($a,0,0,0); $white = imagecolorallocate($a,255,255,255); $gray = imagecolorallocate($a,200,200,200); $red = imagecolorallocate($a,255,0,0); //颜料 imagefill($a,0,0,$red); //填充 for($i=0;$i<20;$i++){ $x = mt_rand(0,100); $y = mt_rand(0,20); imagesetpixel($a,$x,$y,$white); imagesetpixel($a,$x,$y+1,$white); imagesetpixel($a,$x,$y+2,$white); imagesetpixel($a,$x,$y-1,$white); imagesetpixel($a,$x,$y-2,$white); imagesetpixel($a,$x+1,$y,$white); imagesetpixel($a,$x+2,$y,$white); imagesetpixel($a,$x-1,$y,$white); imagesetpixel($a,$x-2,$y,$white); } $z1 = range('a','z'); $z2 = range('A','Z'); $z3 = mt_rand(0,9); $z4 = mt_rand(0,9); imagestring($a,26,25,2,$z1[mt_rand(0,24)],$white); imagestring($a,26,33,2,$z2[mt_rand(0,24)],$white); imagestring($a,26,41,2,$z3,$white); imagestring($a,26,49,2,$z4,$white); header("content-type:image/jpeg"); imagepng($a); //保存 imagejpeg($a); //输出 ?>
//php画库
