index.aspx.cs

C#编的网上交易站点系统。实现购买

using System;
using System.Data;
using System.Configuration;
using System.Web;
using System;
using System.Data;
using System.Collections;


public partial class index_aspx
{
    void Button2_Click(object sender, EventArgs e)
    {
        Response.Redirect("register.aspx");         //若要注册,则转向注册界面
    }
    


    void Button1_Click(object sender, EventArgs e)
    {        
        string name = textname.Text;
        Session["username"] = textname.Text;//用Session["username"]保存用户名,方便以后调用
        if (IsPostBack)
        {
            string pwd = textpwd.Text;
            string sql = "select count(*) from 客户信息表 where 用户名='" +name + "' and 用户密码='" + pwd + "';";//此处为前台提供的SQL语句
            int val = (int)(dal.execscalar(sql));//此处调用后台,查看有无相符的记录,有则返回一,无则返回零
            if (val == 1)//如果存在
            {
                DataTable dt = new DataTable();//创建购物车的过程

                DataColumn dc = new DataColumn();//新建一列
                dc.DataType = System.Type.GetType("System.String");//该列属性
                dc.ColumnName = "花ID";//列名
                dt.Columns.Add(dc);//将列绑定到表中

                dc = new DataColumn();
                dc.DataType = System.Type.GetType("System.Int32");
                dc.ColumnName = "qty";
                dt.Columns.Add(dc);

                dc = new DataColumn();
                dc.DataType = System.Type.GetType("System.Double");
                dc.ColumnName = "价格";
                dt.Columns.Add(dc);

                dc = new DataColumn();
                dc.DataType = System.Type.GetType("System.Double");
                dc.ColumnName = "total";
                dt.Columns.Add(dc);//表定义完毕,共四个属性列
                Session["cart"] = dt;//用 Session["cart"]保存购物车,此时购物车为空
                Response.Redirect("welcome.aspx");//页面转移


            }
            else//若用户不存在
            {
                TextBox2.Visible = true;
                TextBox2.Text = "错误的用户名或密码,请重新输入.";//显示出错信息
            }
        }


    }
    void Page_Load(object sender, EventArgs e)
    {
        Response.Write("当前在线人数为" + Application["number"]);//使用Application对当前在线人数进行统计
        Application.Lock();//先锁定
        Application["online"] = Convert.ToInt32(Application["online"]) + 1;
        Application.UnLock();//再解锁
        Response.Write("您是今天第" + Application["online"]+"位顾客");//显示



    }


    

}