index前台：
<div>
<table style="width: 100%;">
<tr>
<td>
用户名：</td>
<td>
<asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
</td>
</tr>
<tr>
<td>
密码：</td>
<td>
<asp:TextBox ID="TextBox2" runat="server"></asp:TextBox>
</td>
</tr>
<tr>
<td>
验证码：
</td>
<td>
<asp:TextBox ID="TextBox3" runat="server"></asp:TextBox>
<img id="yzm" src="pic.aspx" Xonclick="this.src='pic.aspx?aaa='+new Date()" />
</td>
</tr>
<tr>
<td>
<asp:Button ID="btnLog" runat="server" Xonclick="btnLog_Click" Text="登录" />
</td>
<td>
<asp:Button ID="btnCancle" runat="server" Text="取消" />
</td>
</tr>
</table>
</div>
index后台：
protected void btnLog_Click(object sender, EventArgs e)
{
if (TextBox1.Text.Trim() == "admin" && TextBox2.Text.Trim() == "888888" && Session["YZM"].ToString() == TextBox3.Text.Trim())
{
Response.Write("登录成功！！");
}
else
{
Response.Write("登录失败！！");
}
}
验证码后台：
protected void Page_Load(object sender, EventArgs e)
{
System.Drawing.Image img = new Bitmap(190,50);
Graphics g = Graphics.FromImage(img);
this.AddPoint(img,100);
string code = this.GeneralCode();
Session["YZM"] = code;
Font font1 = new Font("宋体",40,FontStyle.Italic);
g.DrawString(code, font1, Brushes.Red,0,0);
this.Response.Clear();
MemoryStream ms = new MemoryStream();
img.Save(ms, System.Drawing.Imaging.ImageFormat.Jpeg);
this.Response.BinaryWrite(ms.ToArray());
this.Response.Flush();
this.Response.End();
}
private void AddPoint(System.Drawing.Image img, int nums)//加噪点背景
{
Bitmap b = img as Bitmap;
Random ran = new Random();
for (int i = 0; i < nums; i++)
{
b.SetPixel(ran.Next(0,img.Width),ran.Next(0,img.Height),Color.White);
}
}
//生成随机的文字
private string GeneralCode()
{
Random ran = new Random(DateTime.Now.Millisecond);
StringBuilder sb = new StringBuilder(6);
for (int i = 0; i < 6; i++)
{
sb.Append(ran.Next(0,9));
}
return sb.ToString();
}
注册页后台
public partial class zhuce : System.Web.UI.Page, IRequiresSessionState //注意要继承这个类
{
protected void Page_Load(object sender, EventArgs e)
{
}
}
一般处理程序后台
public class YZM : IHttpHandler, IRequiresSessionState //注意要继承这个类
{
public void ProcessRequest(HttpContext context)
{
context.Response.ContentType = "image/jpeg";
//建立Bitmap对象，绘图
Bitmap basemap = new Bitmap(150, 60);
Graphics graph = Graphics.FromImage(basemap);
graph.FillRectangle(new SolidBrush(Color.SkyBlue), 0, 0, 160, 60);
Font font = new Font(FontFamily.GenericSerif, 30, FontStyle.Bold, GraphicsUnit.Pixel);
Random r = new Random();
string letters = "ABCDEFGHIJKLMNPQRSTUVWXYZ";
string letter;
StringBuilder sb = new StringBuilder();
//添加随机的五个字母
for (int x = 0; x < 5; x++)
{
letter = letters.Substring(r.Next(0, letters.Length - 1), 1);
sb.Append(letter);
graph.DrawString(letter, font, new SolidBrush(Color.Tomato), x * 20, r.Next(0, 15));
}
//混淆背景
Pen linePen = new Pen(new SolidBrush(Color.Tomato), 2);
for (int x = 0; x < 6; x++)
graph.DrawLine(linePen, new Point(r.Next(0, 170), r.Next(0, 40)), new Point(r.Next(0, 170), r.Next(0, 40)));
//将图片保存到输出流中
basemap.Save(context.Response.OutputStream, ImageFormat.Gif);
context.Session["CheckCode"] = sb.ToString(); //如果没有实现IRequiresSessionState，则这里会出错，也无法生成图片
context.Response.End();
}
public bool IsReusable
{
get
{
return false;
}
}
}