用户控件

1,添加新项，选择web用户控件，命名为Login.ascx,然后在设计视图中添加几个控件，然后添加table,再添加后台代码，最后添加到其他aspx页面。

(1)下面是html源码：

<%@ Control Language="C#" AutoEventWireup="true" CodeBehind="Login.ascx.cs" Inherits="WebApplication2.userControl.Login" %>

<table>
<tr>
    <td><asp:Label ID="Label1" runat="server" Text="用户名"></asp:Label></td>
    <td><asp:TextBox ID="TxtUserName" runat="server" ></asp:TextBox></td>
</tr>
<tr>
    <td><asp:Label ID="Label2" runat="server" Text="密码"></asp:Label></td>
    <td><asp:TextBox ID="TxtPassword" runat="server"></asp:TextBox></td>
</tr>
<tr>
    <td colspan="2"><asp:CheckBox ID="CheckBox1" Text="是否保持长时间登录状态" runat="server" /></td>
</tr>
<tr>
    <td colspan="2"><asp:Button ID="BtnLogin" runat="server" Text="登录" OnClick="BtnLogin_Click" /></td>
</tr>
    
</table>

(2)下面是后台代码：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Data.SqlClient;
using System.Configuration;

namespace WebApplication2.userControl
{
    public partial class Login : System.Web.UI.UserControl
    {
        SqlConnection conn;
        SqlCommand comm;
        SqlDataReader dreader;

        protected void Page_Load(object sender, EventArgs e)
        {

        }
        protected void BtnLogin_Click(object sender, EventArgs e)
        {
            string username=TxtUserName.Text.Trim();
            string password=TxtPassword.Text.Trim();
            string connStr ="server=.;database=db_OA;uid=sa;pwd=123456" ;//System.Configuration.ConfigurationManager.ConnectionStrings["ConnStr"].ToString();
            conn = new SqlConnection(connStr);
            conn.Open();
            string sql="select * from sysUser where userName=@userName and userPwd=@password";            
            comm = new SqlCommand(sql, conn);
            comm.Parameters.Add(new SqlParameter("@username",username));
            comm.Parameters.Add(new SqlParameter("@password",password));
            dreader = comm.ExecuteReader();
            if (dreader.Read())
            {
                HttpCookie cookie = new HttpCookie("username", username);
                if (CheckBox1.Checked)
                {
                    cookie.Expires = DateTime.Now.AddDays(7);
                }
                Response.Cookies.Add(cookie);
                Response.AppendHeader("refresh", "3,url=WebForm1.aspx");

            }
            else
            {
                
                Response.Write("<script>alert('用户名或密码错误')</script>");
            }
            dreader.Close();
            conn.Close();

        }
      
    }
}

(3)然后把这个用户控件拖拽到其他页面就行了。

这里面很多地方可以通过封装，将属性暴露给外面,如TxtUserName,连接字符串等等。

参考：http://blog.csdn.net/z470208239/article/details/6144713