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。
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
|
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:
1
2
3
4
5
6
|
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。
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
|
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:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
|
<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:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
|
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:
1
2
3
4
5
6
7
8
|
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
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
|
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。