前言：
ObjectDataSource数据源控件优点甚多，确实令人爱不惜手，但不支持重绑定这一项确实让人失望。下面的实战二将通过ObjectDataSource配合GridView来实现删、改、分页、排序，并分析使用cache后排序失灵的原因。
实战：
1.效果：
图1.显示状态
图2.编辑状态
2.代码:
.aspx
1 <asp:ObjectDataSource runat="server" ID="ods" EnablePaging="true" TypeName="OdsDataManager"
2 SelectCountMethod="GetRecordCount" SelectMethod="GetRecord" UpdateMethod="UpdateRecord"
3 DeleteMethod="DelRecord" OnUpdating="ods_OnUpdating" SortParameterName="sortExpression">
5 </asp:ObjectDataSource>
6 <asp:GridView runat="server" ID="gv" DataSourceID="ods" AutoGenerateColumns="false"
7 AllowPaging="true" PageSize="1" AllowSorting="true" DataKeyNames="ID"
8 OnRowDataBound="gv_OnRowDataBound">
9 <HeaderStyle BackColor="graytext" />
10 <Columns>
11 <asp:TemplateField>
12 <HeaderStyle Width="20%" />
13 <HeaderTemplate>
14 <asp:LinkButton runat="server" ID="lbtnSortName" Text="Name" CommandName="Sort" CommandArgument="Name">
15 </asp:LinkButton>
16 </HeaderTemplate>
17 <ItemTemplate><%#Eval("Name") %></ItemTemplate>
18 <EditItemTemplate>
19 <asp:TextBox runat="server" ID="tbxName" Text='<%#Bind("Name") %>'></asp:TextBox>
20 <asp:RegularExpressionValidator runat="server" ID="revName" ControlToValidate="tbxName"
21 ValidationExpression="[a-zA-Z]+" ErrorMessage="Please input your English name!" Display="Dynamic">
22 </asp:RegularExpressionValidator>
23 <asp:RequiredFieldValidator runat="server" ID="rfvName" ControlToValidate="tbxName"
24 ErrorMessage="Please input your name" Display="Dynamic">
25 </asp:RequiredFieldValidator>
26 </EditItemTemplate>
27 </asp:TemplateField>
28 <asp:TemplateField>
29 <HeaderStyle Width="10%"/>
30 <HeaderTemplate>
31 <asp:LinkButton runat="server" ID="lbtnSortSex" Text="Sex" CommandName="Sort" CommandArgument="Sex">
32 </asp:LinkButton>
33 </HeaderTemplate>
34 <ItemTemplate>
35 <asp:RadioButtonList Enabled="false" runat="server" ID="rblSexShow" RepeatDirection="Horizontal"
36 RepeatColumns="2">
37 </asp:RadioButtonList>
38 </ItemTemplate>
39 <EditItemTemplate>
40 <asp:RadioButtonList runat="server" ID="rblSexEdit" RepeatDirection="Horizontal" RepeatColumns="2">
41 </asp:RadioButtonList>
42 </EditItemTemplate>
43 </asp:TemplateField>
44 <asp:TemplateField>
45 <HeaderStyle Width="20%"/>
46 <HeaderTemplate>
47 <asp:LinkButton runat="server" ID="lbtnSortCountry" Text="Country" CommandName="Sort" CommandArgument="Country">
48 </asp:LinkButton>
49 </HeaderTemplate>
50 <ItemTemplate><%#Eval("Country")%></ItemTemplate>
51 <EditItemTemplate>
52 <asp:DropDownList runat="server" ID="ddlCountry"></asp:DropDownList>
53 </EditItemTemplate>
54 </asp:TemplateField>
55 <asp:TemplateField>
56 <HeaderStyle Width="20%"/>
57 <HeaderTemplate>Hobby</HeaderTemplate>
58 <ItemTemplate><%#Eval("Hobby") %></ItemTemplate>
59 <EditItemTemplate>
60 <asp:CheckBoxList runat="server" ID="cbxlHobby" RepeatDirection="Horizontal" RepeatColumns="5">
61 </asp:CheckBoxList>
62 </EditItemTemplate>
63 </asp:TemplateField>
64 <asp:CommandField ShowDeleteButton="true" DeleteText="Delete" ShowEditButton="true" EditText="Edit" />
65 </Columns>
66 <PagerSettings Visible="true" />
67 <PagerStyle Font-Size="12px"/>
68 <PagerTemplate>
69 <div style="float:left;margin-left:15px;color:#999;line-height:20px">
70 当前第<%#this.gv.PageIndex+1 %>/<%#this.gv.PageCount %>页
71 </div>
72 <div style="float:right;margin-right:15px;color:#999;line-height:20px">页</div>
73 <div style="float:right">
74 <asp:DropDownList runat="server" ID="ddlPaging" AutoPostBack="true"
75 OnSelectedIndexChanged="ddlPaging_OnSelectedIndexChanged">
76 </asp:DropDownList>
77 </div>
78 <div style="float:right;color:#999;line-height:20px">跳转到第</div>
79 </PagerTemplate>
80 </asp:GridView>
说明：
1.因用了数据源控件，所以Name在编辑状态时使用<%#Bind("Name")%>来实现双向通讯的绑定
2.因为没有添加的功能，所以用了asp:CommandField来实现编辑、删除等按钮的功能。
3.排序功能上只要在ods上设定SortParameterName，它的值就是SelectMethod中关于排序的参数的名称，然后设定GridView的AllowSorting为true就ok了。排序按钮上依然用到GridView内置的CommandName——Sort，然后CommandArgument设为要排序的字段名，至于排序的方向由ObjectDataSource负责，省心多了。
.aspx.cs代码
1 public partial class Default2 : System.Web.UI.Page
2 {
3 private OdsDataManager dm = new OdsDataManager();
4
5 protected void Page_Load(object sender, EventArgs e)
6 {
7
8 }
9
10 protected void gv_OnRowDataBound(object sender, GridViewRowEventArgs e)
11 {
12 DataRowView drv = e.Row.DataItem as DataRowView;
13
14 if (e.Row.RowType == DataControlRowType.DataRow)
15 {
16 //显示时
17 if (this.gv.EditIndex == -1)
18 {
19 //设置性别
20 RadioButtonList rbl = e.Row.FindControl("rblSexShow") as RadioButtonList;
21 rbl.Items.Add(new ListItem("Male", "M"));
22 rbl.Items.Add(new ListItem("Female", "F"));
23 if ((drv["Sex"] as string).ToLower().Equals("m"))
24 rbl.Items[0].Selected = true;
25 else
26 rbl.Items[1].Selected = true;
27 }
28 //修改时：
29 else if (e.Row.RowIndex == this.gv.EditIndex)
30 {
31 //性别
32 RadioButtonList rbl = e.Row.FindControl("rblSexEdit") as RadioButtonList;
33 rbl.Items.Add(new ListItem("Male", "M"));
34 rbl.Items.Add(new ListItem("Female", "F"));
35 if ((drv["Sex"] as string).ToLower().Equals("m"))
36 rbl.Items[0].Selected = true;
37 else
38 rbl.Items[1].Selected = true;
39 //国籍
40 DropDownList ddlCountry = e.Row.FindControl("ddlCountry") as DropDownList;
41 DataTable countryDt = dm.GetCountry();
42 ListItem li = null;
43 for (int i = 0; i < countryDt.Rows.Count; ++i)
44 {
45 string cn = countryDt.Rows[i]["cn"] as string;
46 li = new ListItem(cn, cn);
47 if (cn.Equals(drv["Country"] as string))
48 li.Selected = true;
49 ddlCountry.Items.Add(li);
50 }
51 //兴趣
52 CheckBoxList cbl = e.Row.FindControl("cbxlHobby") as CheckBoxList;
53 DataTable hobbyDt = dm.GetHobby();
54 string hobbys = drv["Hobby"] as string;
55 ListItem hobbyLi = null;
56 string hstr = string.Empty;
57 for (int i = 0; i < hobbyDt.Rows.Count; i++)
58 {
59 hstr = hobbyDt.Rows[i]["hobby"] as string;
60 hobbyLi = new ListItem(hstr, hstr);
61 if (hobbys.IndexOf(hstr) >= 0)
62 hobbyLi.Selected = true;
63 cbl.Items.Add(hobbyLi);
64 }
65 }
66 }
67 else if (e.Row.RowType == DataControlRowType.Pager)
68 {
69 //绑定分页控件
70 DropDownList ddlPaging = e.Row.FindControl("ddlPaging") as DropDownList;
71 for (int i = 0; i < this.gv.PageCount; i++)
72 {
73 ddlPaging.Items.Add(new ListItem(Convert.ToString(i + 1), Convert.ToString(i)));
74 }
75 ddlPaging.SelectedIndex = this.gv.PageIndex;
76 }
77 }
78
79 /// <summary>
80 /// 分页控件的OnSelectedIndexChanged
81 /// </summary>
82 /// <param name="sender"></param>
83 /// <param name="e"></param>
84 protected void ddlPaging_OnSelectedIndexChanged(object sender, EventArgs e)
85 {
86 this.gv.PageIndex = (sender as DropDownList).SelectedIndex;
87 }
88
89 protected void ods_OnUpdating(object sender, ObjectDataSourceMethodEventArgs e)
90 {
91 string Sex = (this.gv.Rows[this.gv.EditIndex].FindControl("rblSexEdit") as RadioButtonList).SelectedValue;
92 string Country = (this.gv.Rows[this.gv.EditIndex].FindControl("ddlCountry") as DropDownList).SelectedValue;
93 System.Text.StringBuilder hobbys = new System.Text.StringBuilder();
94 foreach (ListItem li in (this.gv.Rows[this.gv.EditIndex].FindControl("cbxlHobby") as CheckBoxList).Items)
95 {
96 if (li.Selected)
97 hobbys.Append(li.Value+",");
98 }
99 if (hobbys.Length >= 2)
100 hobbys.Remove(hobbys.Length - 1, 1);
101
102 e.InputParameters.Add("Sex", Sex);
103 e.InputParameters.Add("Country", Country);
104 e.InputParameters.Add("Hobby",hobbys.ToString());
105 }
106 }
说明：
1.看到behind code是不是发现代码量少了很多呢？这就是用ods的好处了。
2.在更新操作时，因为Country、Sex和Hobby都没有和ods作双向绑定，所以要自己获取并写入到ods的InputParameters中，然后ods就会调用已经设置好的UpdateMethod了。
数据操作类
1 public class OdsDataManager
2 {
3 private static DataTable dt = null;//用户记录
4 private static DataTable countryDt = null;//国籍
5 private static DataTable hobbyDt = null;//兴趣
6
7 public OdsDataManager()
8 {
9 if (dt == null)
10 {
11 dt = new DataTable();
12 dt.Columns.Add("ID");
13 dt.Columns.Add("Name");
14 dt.Columns.Add("Sex");
15 dt.Columns.Add("Country");
16 dt.Columns.Add("Hobby");
17
18 //Default Data
19 dt.Rows.Add(new object[] { 1, "Mary", "F", "China", "Cooking,Music" });
20 dt.Rows.Add(new object[] { 2, "John", "M", "China", "Tennis" });
21 }
22
23 if (countryDt == null)
24 {
25 countryDt = new DataTable();
26 countryDt.Columns.Add("cn");
27
28 //Default Data
29 countryDt.Rows.Add(new object[] { "China" });
30 countryDt.Rows.Add(new object[] { "French" });
31 countryDt.Rows.Add(new object[] { "America" });
32 countryDt.Rows.Add(new object[] { "Afria" });
33 countryDt.Rows.Add(new object[] { "Japan" });
34 }
35
36 if (hobbyDt == null)
37 {
38 hobbyDt = new DataTable();
39 hobbyDt.Columns.Add("hobby");
40
41 //Default Data
42 hobbyDt.Rows.Add(new object[] { "Cooking" });
43 hobbyDt.Rows.Add(new object[] { "Music" });
44 hobbyDt.Rows.Add(new object[] { "Reading" });
45 hobbyDt.Rows.Add(new object[] { "Movies" });
46 hobbyDt.Rows.Add(new object[] { "Tennis" });
47 }
48 }
49
50 public DataTable GetRecord(int maximumRows, int startRowIndex, string sortExpression)
51 {
52 //排序
53 if(!string.IsNullOrEmpty(sortExpression))
54 {
55 dt.DefaultView.Sort = sortExpression;
56 }
57
58 DataRow[] drs = dt.Select();
59 DataTable dt1 = dt.Clone();
60 for (int i = startRowIndex; i < startRowIndex+maximumRows && i<drs.Length; i++)
61 {
62 dt1.Rows.Add(drs[i].ItemArray);
63 }
64
65 return dt1;
66 }
67
68 public int GetRecordCount()
69 {
70 return dt.Rows.Count;
71 }
72
73 public bool UpdateRecord(int ID, string Name, string Sex, string Country, string Hobby)
74 {
75 bool result = false;
76 DataRow[] drs = dt.Select("ID=" + ID);
77 if (drs.Length == 1)
78 {
79 drs[0]["Name"] = Name;
80 drs[0]["Sex"] = Sex;
81 drs[0]["Country"] = Country;
82 drs[0]["Hobby"] = Hobby;
83
84 result = true;
85 }
86
87 return result;
88 }
89
90 public bool DelRecord(int ID)
91 {
92 bool result = false;
93 DataRow[] drs = dt.Select("ID=" + ID);
94 if (drs.Length == 1)
95 {
96 dt.Rows.Remove(drs[0]);
97
98 result = true;
99 }
100
101 return result;
102 }
103
104 public DataTable GetCountry()
105 {
106 return countryDt;
107 }
108
109 public DataTable GetHobby()
110 {
111 return hobbyDt;
112 }
113 }
说明：
1.GetRecord方法绑定到ods的SelectMethod上，因为启用分页和排序功能，所以参数数组中必须有maximumRows（每页记录数）, startRowIndex（当前页首条记录在整个数据集中的索引）, sortExpression（排序表达式，首次加载页面时为空字符串，postback时含排序字段和排序方向）。
3.数据缓存
ods可以启用cache，该cache为应用程序级的，就是多个画面的ods只要SelectMethod和SelectCountMethod、Select参数一样就可以共享缓存中的数据，在Cache有效时进行Select操作将会先根据前面说的三个要素从Cache中获取数据，如果没有才执行SelectMethod方法。注意不同的要素组合会各自对应一份缓存的数据，当第二次请求时就直接读缓存。
就是因为这样问题就来了，如果启用了cache那么上面的排序功能就会失效，而其他功能依然正常。原因在于排序操作是在SelectMethod中实现，而在Cache生效时程序根本就不执行SelectMethod方法，除非说内存不足或其他原因令cache不够大来保存数据而被迫执行SelectMethod方法。对于该问题目前还没找到解决的方法，望大哥们来告诉我啦^_^
好消息：对于上面的问题终于找到了解决方法，就是自定义一个缓存层而不使用ods附带的缓存功能。具体请看：http://www.cnblogs.com/fsjohnhuang/archive/2011/12/19/2292947.html
如果您觉得本文的内容有趣就扫一下吧！捐赠互勉！
本文转自^_^肥仔John博客园博客，原文链接：http://www.cnblogs.com/fsjohnhuang/archive/2011/12/17/2291118.html，如需转载请自行联系原作者
