log.aspx
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title></title>
<script src="../../Scripts/jquery-1.4.1.min.js" type="text/javascript"></script>//
//可以使用微软自带的jqury.js 下面jquery-1.4.1.min.js版本之上的。或者在jquery官网上下载就可以。
<script type="text/javascript" language="javascript"> //重新获取验证字符
function changeImage() { //单击触发图片重载事件，完成图片验证码的更换
document.getElementById("img").src = document.getElementById("img").src + '?'; //其中imgRandom为验证码图片的id。
}
</script>
</head>
<body>
<form id="form1" runat="server">
<div>
<asp:TextBox ID="txtcode" runat="server"></asp:TextBox>
<img src="ValidateCode.aspx" id="img" onclick="f_refreshtype()" width="50px"/>
<a href="javascript:changeImage();">看不清?</a>
<a href="#" onclick="img.src='ValidateCode.aspx?t='+(new Date().getTime());return false;">看不清，换一张？</a>
<asp:Button ID="Button1" runat="server" Text="Button" onclick="Button1_Click" />
</div>
</form>
</body>
</html>
log.aspx.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
public partial class mb_yanzhengma_log : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
}
protected void Button1_Click(object sender, EventArgs e)
{
string usercode = txtcode.Text.Trim();
if (usercode == Session["vcode"].ToString())//Session["vcode"]
{
Response.Write("OK,正确");
}
else
{
Response.Write("验证码不符合");
}
}
}
新建ValidateCode.aspx页面
ValidateCode.aspx.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Drawing;
using System.Drawing.Imaging;
public partial class mb_yanzhengma_ValidateCode : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
string validateCode = CreateValidateCode();//生成验证码
Bitmap bitmap = new Bitmap(imgWidth, imgHeight);//生成Bitmap图像
DisturbBitmap(bitmap); //图像背景
DrewValidateCode(bitmap, validateCode);//绘制验证码图像
bitmap.Save(Response.OutputStream, ImageFormat.Gif);//保存图像，等待输出
}
private int codeLen = 4;//验证码长度
private int fineness = 85;//图片清晰度
private int imgWidth = 48;//图片宽度
private int imgHeight = 24;//图片高度
private string fontFamily = "Times New Roman";//字体名称
private int fontSize = 14;//字体大小
//private int fontStyle = 0;//字体样式
private int posX = 0;//绘制起始坐标X
private int posY = 0;//绘制坐标Y
private string CreateValidateCode() //生成验证码
{
string validateCode = "";
Random random = new Random();// 随机数对象
for (int i = 0; i < codeLen; i++)//循环生成每位数值
{
int n = random.Next(10);//数字
validateCode += n.ToString();
}
Session["vcode"] = validateCode;//保存验证码 这Session是在前台调用的。
return validateCode;// 返回验证码
}
private void DisturbBitmap(Bitmap bitmap)//图像背景
{
Random random = new Random();//通过随机数生成
for (int i = 0; i < bitmap.Width; i++)//通过循环嵌套，逐个像素点生成
{
for (int j = 0; j < bitmap.Height; j++)
{
if (random.Next(90) <= this.fineness)
bitmap.SetPixel(i, j, Color.LightGray);
}
}
}
private void DrewValidateCode(Bitmap bitmap, string validateCode)//绘制验证码图像
{
Graphics g = Graphics.FromImage(bitmap);//获取绘制器对象
Font font = new Font(fontFamily, fontSize, FontStyle.Bold);//设置绘制字体
g.DrawString(validateCode, font, Brushes.Black, posX, posY);//绘制验证码图像
}
}
