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  • ASP.NET购物车实现过程详解
  • 2020/4/20 10:58:12
  • 本文实例为大家分享了ASP.NET实现购物车的具体代码,供大家参考,具体内容如下

    1、 将test数据库附加到数据库管理系统中;数据库中的book_info包含下列数据:

    2、 新建一个网站,将images文件夹复制到网站中;

    3、 在Default.aspx中,通过DataList控件展示数据库中的所有数据,以行为主序,每行3列,单击购买按钮时,将商品的ID和数量保存到HashTable中,并将HashTable放置到Session中。

    protected void DataList1_ItemCommand(object source, DataListCommandEventArgs e) 
     { 
      string id = e.CommandArgument.ToString(); 
      Hashtable ht; 
      if (Session["shopcar"] == null) 
      { 
       ht = new Hashtable(); 
       ht.Add(id, 1); 
       Session["shopcar"] = ht; 
      } 
      else 
      { 
       ht = (Hashtable)Session["shopcar"]; 
       if (ht.Contains(id)) 
       { 
        int count = int.Parse(ht[id].ToString()); 
        ht[id] = count + 1; 
        Session["shopcar"] = ht; 
        Response.Write(count + 1); 
       } 
       else 
       { 
        ht.Add(id, 1); 
        Session["shopcar"] = ht; 
       } 
      } 
     } 

    4、 在Default.aspx中添加一个超链接,链接到shopcart.aspx,在shopcart.aspx中显示用户购买的商品信息。
    提示:

    A、在shopcart中先定义下列变量:

    Hashtable ht;
     DataTable dt;
     string connstring=@"DataSource=.\SQLEXPRESS;Initial Catalog=test;Integrated Security=True";
     SqlConnection conn;
     SqlCommand cmd;
     SqlDataReader sdr;
    

    B、页面中添加一个GridView。
    C、在page_load中,将dt实例化,建立各列。

    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("<script>if(confirm('你没有登录')window.location='Default15.aspx';else window.close();</script>");
      }
      else
      {
       ht = (Hashtable)Session["shopcar"];
       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:GridView ID="GridView1" runat="server" AutoGenerateColumns="False">
       <Columns>
        <asp:BoundField DataField="id" HeaderText="ID" />
        <asp:BoundField DataField="name" HeaderText="名称" />
        <asp:BoundField DataField="price" HeaderText="价格" />
        <asp:TemplateField>   
        <ItemTemplate>
         <asp:TextBox runat="server" ID="textbox1" Text='<%# Eval("Num") %>'
          ontextchanged="textbox1_TextChanged" AutoPostBack="True" ></asp:TextBox>
        </ItemTemplate>   
        </asp:TemplateField>
       <asp:BoundField DataField="total" HeaderText="总计" />
       <asp:TemplateField>
        <ItemTemplate>
        <asp:Button runat="server" ID="button1" CommandArgument='<%# Eval("id") %>'
          Text="删除" onclick="button1_Click" />
        
        </ItemTemplate>
       
       </asp:TemplateField>
       </Columns>   
      </asp:GridView>

    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+"<br />");
       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:
    
    \\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("<script>if(confirm('你没有登录')window.location='Default.aspx';else window.close();</script>"); 
      } 
      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) 
     { 
      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 + "<br />"); 
       ht[id] = num; 
      } 
      Session["shopcar"] = ht; 
      Bind(); 
     
     } 
     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(); 
     
     } 
    } 
    

    制作一个简单的购物车就是这么简单,大家可以按照我的思路进行创作,在此基础上在添加一些功能。