<?php/** * Created by PhpStorm. * User: user * Date: 16-5-27 * Time: 上午8:25 */header("Content-type: image/gif;charset=utf-8");$x=100;$y=30;$im = imagecreate($x,$y);$black =ImageColorAllocate ($im, 0,0,0);$white = ImageColorAllocate($im, 0,255,255);//ImageTTFText($im, 15, 0, 30, 20, $white, "ARIALNI.TTF", "Hello World");//随机五位数字//$num=rand(1,9);//for($i=0;$i<5;$i++){// $num.=rand(1,9);//}$num=getRandChar(4);//把验证码保存到session当中 以便于用户登录时验证是否正确session_start();$_SESSION['code']=$num;ImageTTFText($im, 15, 0, 30, 20, $white, "ARIALNI.TTF", $num);//添加干扰线 可以使用循环for($i=0;$i<5;$i++) { $lineColor = imagecolorallocate($im, rand(0, 255), rand(0, 255), rand(0, 255)); //imageline($im, rand(0, 5), 0, rand(0, 5), 30, $lineColor); imageline($im, rand(0,$x), 0, rand(0,$x),$y, $lineColor);}//添加干扰点for($i=0;$i<100;$i++){ imagesetpixel($im,rand(0,$x),rand(0,$y),$lineColor);}ImageGif($im);ImageDestroy($im);function getRandChar($length){ $str = null; $strPol = "123456789"; $max = strlen($strPol)-1; for($i=0;$i<$length;$i++){ $str.=$strPol[rand(0,$max)];//rand($min,$max)生成介于min和max两个数之间的一个随机整数 } return $str;}?>