备注:将公共页面加入session_start();
session_start();
ini_set('display_errors', 'Off');
class CCheckCodeFile
{
//验证码位数 www.2cto.com
var $mCheckCodeNum = 4;
//产生的验证码
var $mCheckCode = '';
//验证码的图片
var $mCheckImage = '';
//干扰像素
var $mDisturbColor = '';
//验证码的图片宽度
var $mCheckImageWidth = '80';
//验证码的图片宽度
var $mCheckImageHeight = '20';
//输出头
function OutFileHeader()
{
header ("Content-type: image/png");
}
//产生验证码
function CreateCheckCode()
{
//$this->mCheckCode = strtoupper(substr(md5(rand()),0,$this->mCheckCodeNum));
$this->mCheckCode = strtoupper(substr(rand(0,9999999999),0,$this->mCheckCodeNum));
session_cache_expire(60);
session_start();
$_SESSION["code_str"] = $this->mCheckCode;
return $this->mCheckCode;
}
//产生验证码图片
function CreateImage()
{
$this->mCheckImage = @imagecreate ($this->mCheckImageWidth,$this->mCheckImageHeight);
imagecolorallocate ($this->mCheckImage, 255, 255, 255);
return $this->mCheckImage;
}
//设置图片的干扰像素
function SetDisturbColor()
{
for ($i=0;$i
{
$this->mDisturbColor = imagecolorallocate ($this->mCheckImage, rand(0,255), rand(0,255), rand(0,255));
imagesetpixel($this->mCheckImage,rand(1,100),rand(1,100),$this->mDisturbColor);
}
}
//设置验证码图片的大小\宽\高
function SetCheckImageWH($width,$height)
{
if($width==''||$height=='')return false;
$this->mCheckImageWidth = $width;
$this->mCheckImageHeight = $height;
return true;
}
//在验证码图片上逐个画上验证码
function WriteCheckCodeToImage()
{
for ($i=0;$imCheckCodeNum;$i++)
{
$bg_color = imagecolorallocate ($this->mCheckImage, rand(0,255), rand(0,255), rand(0,255));
$x = floor($this->mCheckImageWidth/$this->mCheckCodeNum)*$i;
$y = rand(0,$this->mCheckImageHeight-15);
imagechar ($this->mCheckImage, 5, $x, $y, $this->mCheckCode[$i], $bg_color);
}
}
//输出验证码图片
function OutCheckImage()
{
$this ->OutFileHeader();
$this ->CreateCheckCode();
$this ->CreateImage();
$this ->SetDisturbColor();
$this ->WriteCheckCodeToImage();
imagepng($this->mCheckImage);
imagedestroy($this->mCheckImage);
}
}
$c_check_code_image = new CCheckCodeFile();
//$c_check_code_image ->SetCheckImageWH(100,50);//设置显示验证码图片的尺寸
$c_check_code_image->OutCheckImage();
?>
使用方法:
验证是否正确
session_start();
if($_POST["number"] == $_SESSION["code_str"]){
// echo("验证码正确");
}else{
echo "
var s=10;
function ok()
{
s--;
document.getElementById('tips').innerHTML=s;
if(s==0)
{
clearTimeout(t);
history.go(-1);
}
}
var t=setInterval('ok()',1000);
" . "请输入的验证码,请重新输入秒之后，将为您跳转到上一页";
}
摘自 http://itsafe.org/?p=384
