ASP(1)，怒斩腾讯和阿里的Offer
foreach **(**object item in ht.Keys)
{
string id = item.ToString();
int num = int.Parse(ht[item].ToString());
string sql = “selectbook_name,price from book_info where book_id=’” + id + “’”;
conn = new SqlConnection**(connstring);**
cmd = new SqlCommand**(sql, conn);**
conn.Open();
sdr =cmd.ExecuteReader();
if (sdr.HasRows)
{
sdr.Read();
DataRow row = dt.NewRow();
row[“id”] = id;
row[“Num”] = num;
row[“name”] = sdr.GetString(0);
row[“price”**] =**float.Parse(sdr[1].ToString());
row[“total”**] =num*(**float.Parse(sdr[1].ToString()));
dt.Rows.Add(row);
}
sdr.Close();
conn.Close();
}
GridView1.DataSource = dt.DefaultView;
GridView1.DataBind();
}
}
D、这时可以看到用户购买的商品，但不能修改数量，也不能删除。
E、添加修改数量，删除商品功能，在aspx页面中定义GridView中的各列：
asp:TemplateField\
ontextchanged=“textbox1_TextChanged” AutoPostBack=“True” >
asp:TemplateField\
Text=“删除” οnclick=“button1_Click” />
F、为GridView中的文本框添加TextChanged事件：
protected void **textbox1_TextChanged(**object sender, EventArgs e)
{
Hashtable ht =(Hashtable)Session[“shopcar”];
if (ht == null**)** return**;**
for **(**int i = 0; i < GridView1.Rows.Count;i++)
{
string id =GridView1.Rows[i].Cells[0].Text.ToString();
Response.Write(id);
string num = ((TextBox)GridView1.Rows[i].FindControl(“textbox1”)).Text;
Response.Write(" “+num+”
");
ht[id] = num;
}
Session[“shopcar”] = ht;
Bind();
}
G、为按钮添加单击事件：
protected void **button1_Click(**object sender, EventArgs e)
{
string id = ((Button)sender).CommandArgument;
Hashtable ht = (Hashtable)Session[“shopcar”];
if (ht == null**)** return**;**
ht.Remove(id);
Bind();
}
购物车代码：showcart.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.Collections;
using System.Data;
using System.Data.SqlClient;
public partial class shopcart : System.Web.UI.Page
{
Hashtable ht;
DataTable dt;
string connstr = “Data Source=.\SQLEXPRESS;AttachDbFilename=F:\大三课程\ASP.Net程序设计\实验\实验7要求与素材\test.mdf;Integrated Security=True;Connect Timeout=30;User Instance=True”;
SqlConnection conn;
SqlCommand cmd;
SqlDataReader sdr;
protected void Page_Load(object sender, EventArgs e)
{
dt = new DataTable();
DataColumn col = new DataColumn();
col.ColumnName = “id”;
col.DataType = System.Type.GetType(“System.String”);
dt.Columns.Add(col);
col = new DataColumn();
col.ColumnName = “name”;
col.DataType = System.Type.GetType(“System.String”);
dt.Columns.Add(col);
col = new DataColumn();
col.ColumnName = “Num”;
col.DataType = System.Type.GetType(“System.Int32”);
dt.Columns.Add(col);
col = new DataColumn();
col.ColumnName = “price”;
col.DataType = System.Type.GetType(“System.Single”);
dt.Columns.Add(col);
col = new DataColumn();
col.ColumnName = “Total”;
col.DataType = System.Type.GetType(“System.Single”);
dt.Columns.Add(col);
if (!IsPostBack)
{
Bind();
}
}
public void Bind()
{
if (Session[“shopcar”] == null)
{
Response.Write(“”);
}
else
{
ht = (Hashtable)Session[“shopcar”];
foreach (object item in ht.Keys)
{
string id = item.ToString();
int num = int.Parse((ht[item].ToString()));
string sql = “select book_name,price from book_info where book_id=’” + id + “’”;
conn = new SqlConnection(connstr);
cmd = new SqlCommand(sql, conn);
conn.Open();
sdr = cmd.ExecuteReader();
if (sdr.HasRows)
{
sdr.Read();
DataRow row = dt.NewRow();
row[“id”] = id;
row[“Num”] = num;
row[“name”] = sdr.GetString(0);
row[“price”] = float.Parse(sdr[1].ToString());
row[“total”] = num * (float.Parse(sdr[1].ToString()));
dt.Rows.Add(row);
}
sdr.Close();
conn.Close();
}
}
GridView1.DataSource = dt.DefaultView;
GridView1.DataBind();
}
protected void textbox1_TextChanged(
object sender, EventArgs e)
{
{
sdr.Read();
DataRow row = dt.NewRow();
row[“id”] = id;
row[“Num”] = num;
row[“name”] = sdr.GetString(0);
row[“price”] = float.Parse(sdr[1].ToString());
row[“total”] = num * (float.Parse(sdr[1].ToString()));
dt.Rows.Add(row);
}
sdr.Close();
conn.Close();
}
}
GridView1.DataSource = dt.DefaultView;
GridView1.DataBind();
}
protected void textbox1_TextChanged([外链图片转存中…(img-FmUzgsjG-1641798764000)]
object sender, EventArgs e)
{