datagrid嵌套和资源消耗

datagrid嵌套的文章很多了。

我这里参考的是以下两篇

http://www.cnblogs.com/lovecherry/archive/2005/04/26/145633.html

http://www.microsoft.com/china/MSDN/library/data/dataAccess/NestGridHierData.mspx

我只是做了datagrid的嵌套，并没有动态添加模板列那么复杂。

最后的代码给大家。有一部分是vs生成的，懒的写。

<% @ Page language="c#" Codebehind="WebForm2.aspx.cs" AutoEventWireup="false" Inherits="test1.WebForm2"  %>
<! DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"  >
< HTML >
     < HEAD >
         < title > WebForm2 </ title >
         < meta  content ="Microsoft Visual Studio .NET 7.1"  name ="GENERATOR" >
         < meta  content ="C#"  name ="CODE_LANGUAGE" >
         < meta  content ="JavaScript"  name ="vs_defaultClientScript" >
         < meta  content ="http://schemas.microsoft.com/intellisense/ie5"  name ="vs_targetSchema" >
     </ HEAD >
     < body >
         < form  id ="Form1"  method ="post"  runat ="server" >
             < asp:datagrid  id =DataGrid1  runat ="server"  AutoGenerateColumns ="False"  DataSource ="<%# dataSet1 %>" >
                 < Columns >
                     < asp:BoundColumn  DataField ="EmployeeID"  HeaderText ="编号" ></ asp:BoundColumn >
                     < asp:TemplateColumn  HeaderText ="测试列" >
                         < ItemTemplate >
                             < asp:DataGrid  id ="DataGrid2"  runat ="server"  AutoGenerateColumns ="False" >
                                 < Columns >
                                     < asp:BoundColumn  DataField ="TerritoryID"  HeaderText ="编号" ></ asp:BoundColumn >
                                 </ Columns >
                             </ asp:DataGrid >
                         </ ItemTemplate >
                     </ asp:TemplateColumn >
                 </ Columns >
             </ asp:datagrid >
             < asp:DataGrid  id ="DataGrid3"  runat ="server"  AutoGenerateColumns ="False" >
                 < Columns >
                     < asp:BoundColumn  DataField ="TerritoryID"  HeaderText ="标号" ></ asp:BoundColumn >
                 </ Columns >
             </ asp:DataGrid ></ form >
     </ body >
</ HTML >

using  System;
using  System.Collections;
using  System.ComponentModel;
using  System.Data;
using  System.Data.SqlClient;
using  System.Drawing;
using  System.Web;
using  System.Web.SessionState;
using  System.Web.UI;
using  System.Web.UI.WebControls;
using  System.Web.UI.HtmlControls;

namespace  test1
{
    /**//// <summary>
    /// WebForm2 的摘要说明。
    /// </summary>
    public class WebForm2 : System.Web.UI.Page
    {
        protected System.Data.SqlClient.SqlDataAdapter sqlDataAdapter1;
        protected System.Data.SqlClient.SqlCommand sqlSelectCommand1;
        protected System.Data.SqlClient.SqlCommand sqlInsertCommand1;
        protected System.Data.SqlClient.SqlCommand sqlUpdateCommand1;
        protected System.Data.SqlClient.SqlCommand sqlDeleteCommand1;
        protected System.Data.SqlClient.SqlConnection sqlConnection1;
        protected System.Data.DataSet dataSet1;
        protected System.Web.UI.WebControls.DataGrid DataGrid3;
        protected System.Web.UI.WebControls.DataGrid DataGrid1;
    
        private void Page_Load(object sender, System.EventArgs e)
        {
            // 在此处放置用户代码以初始化页面
            if(!IsPostBack)
            {
                sqlDataAdapter1.Fill(dataSet1);

                DataGrid3.DataSource=BindGrid2(1);

                DataGrid1.DataBind();
                DataGrid3.DataBind();
            
            }
        }

        Web 窗体设计器生成的代码#region Web 窗体设计器生成的代码
        override protected void OnInit(EventArgs e)
        {
            //
            // CODEGEN: 该调用是 ASP.NET Web 窗体设计器所必需的。
            //
            InitializeComponent();
            base.OnInit(e);
        }
        
        /**//// <summary>
        /// 设计器支持所需的方法 - 不要使用代码编辑器修改
        /// 此方法的内容。
        /// </summary>
        private void InitializeComponent()
        {    
            this.sqlDataAdapter1 = new System.Data.SqlClient.SqlDataAdapter();
            this.sqlDeleteCommand1 = new System.Data.SqlClient.SqlCommand();
            this.sqlConnection1 = new System.Data.SqlClient.SqlConnection();
            this.sqlInsertCommand1 = new System.Data.SqlClient.SqlCommand();
            this.sqlSelectCommand1 = new System.Data.SqlClient.SqlCommand();
            this.sqlUpdateCommand1 = new System.Data.SqlClient.SqlCommand();
            this.dataSet1 = new System.Data.DataSet();
            ((System.ComponentModel.ISupportInitialize)(this.dataSet1)).BeginInit();
            // 
            // sqlDataAdapter1
            // 
            this.sqlDataAdapter1.DeleteCommand = this.sqlDeleteCommand1;
            this.sqlDataAdapter1.InsertCommand = this.sqlInsertCommand1;
            this.sqlDataAdapter1.SelectCommand = this.sqlSelectCommand1;
            this.sqlDataAdapter1.TableMappings.AddRange(new System.Data.Common.DataTableMapping[] {
                                                                                                      new System.Data.Common.DataTableMapping("Table", "Employees", new System.Data.Common.DataColumnMapping[] {
                                                                                                                                                                                                                   new System.Data.Common.DataColumnMapping("EmployeeID", "EmployeeID")})});
            this.sqlDataAdapter1.UpdateCommand = this.sqlUpdateCommand1;
            // 
            // sqlDeleteCommand1
            // 
            this.sqlDeleteCommand1.CommandText = "DELETE FROM Employees WHERE (EmployeeID = @Original_EmployeeID)";
            this.sqlDeleteCommand1.Connection = this.sqlConnection1;
            this.sqlDeleteCommand1.Parameters.Add(new System.Data.SqlClient.SqlParameter("@Original_EmployeeID", System.Data.SqlDbType.Int, 4, System.Data.ParameterDirection.Input, false, ((System.Byte)(0)), ((System.Byte)(0)), "EmployeeID", System.Data.DataRowVersion.Original, null));
            // 
            // sqlConnection1
            // 
            this.sqlConnection1.ConnectionString = "workstation id=李征;packet size=4096;user id=fa;pwd=fa;data source=李征;persist secur" +
                "ity info=False;initial catalog=Northwind";
            // 
            // sqlInsertCommand1
            // 
            this.sqlInsertCommand1.CommandText = "INSERT INTO Employees() VALUES (); SELECT EmployeeID FROM Employees WHERE (Employ" +
                "eeID = @@IDENTITY)";
            this.sqlInsertCommand1.Connection = this.sqlConnection1;
            // 
            // sqlSelectCommand1
            // 
            this.sqlSelectCommand1.CommandText = "SELECT EmployeeID FROM Employees";
            this.sqlSelectCommand1.Connection = this.sqlConnection1;
            // 
            // sqlUpdateCommand1
            // 
            this.sqlUpdateCommand1.CommandText = "UPDATE Employees SET WHERE (EmployeeID = @Original_EmployeeID); SELECT EmployeeID" +
                " FROM Employees WHERE (EmployeeID = @EmployeeID)";
            this.sqlUpdateCommand1.Connection = this.sqlConnection1;
            this.sqlUpdateCommand1.Parameters.Add(new System.Data.SqlClient.SqlParameter("@Original_EmployeeID", System.Data.SqlDbType.Int, 4, System.Data.ParameterDirection.Input, false, ((System.Byte)(0)), ((System.Byte)(0)), "EmployeeID", System.Data.DataRowVersion.Original, null));
            this.sqlUpdateCommand1.Parameters.Add(new System.Data.SqlClient.SqlParameter("@EmployeeID", System.Data.SqlDbType.Int, 4, "EmployeeID"));
            // 
            // dataSet1
            // 
            this.dataSet1.DataSetName = "NewDataSet";
            this.dataSet1.Locale = new System.Globalization.CultureInfo("zh-CN");
            this.DataGrid1.ItemCommand += new System.Web.UI.WebControls.DataGridCommandEventHandler(this.DataGrid1_ItemCommand);
            this.DataGrid1.ItemDataBound += new System.Web.UI.WebControls.DataGridItemEventHandler(this.DataGrid1_ItemDataBound);
            this.Load += new System.EventHandler(this.Page_Load);
            ((System.ComponentModel.ISupportInitialize)(this.dataSet1)).EndInit();

        }
        #endregion

        private void DataGrid1_ItemCommand(object source, System.Web.UI.WebControls.DataGridCommandEventArgs e)
        {
        }

        private DataView BindGrid2(int EmployeeID)
        {
            SqlConnection myconn=new SqlConnection();
            myconn.ConnectionString="workstation id=李征;packet size=4096;user id=fa;pwd=fa;data source=李征;persist secur" +
                "ity info=False;initial catalog=Northwind";

            SqlDataAdapter myda=new SqlDataAdapter("select TerritoryID from EmployeeTerritories where EmployeeID="+EmployeeID.ToString(),myconn);

            DataSet ds=new DataSet();

            myda.Fill(ds);

            return ds.Tables[0].DefaultView;
        }

        private void DataGrid1_ItemDataBound(object sender, System.Web.UI.WebControls.DataGridItemEventArgs e)
        {
            if ( e.Item.ItemType == ListItemType.Item || e.Item.ItemType == ListItemType.AlternatingItem)
            {
                DataGrid dgt = (DataGrid)e.Item.FindControl("DataGrid2");

                dgt.DataSource=BindGrid2(int.Parse(e.Item.Cells[0].Text.ToString()));
                dgt.DataBind();

                //Label lb=(Label)e.Item.FindControl("l1");

                //lb.Text="111";

            }

        }
    }
}

挑重点看看吧。。。

再说到资源消耗，这么嵌套真有点资源杀手的味道。大部分资源都消耗在对控件的消耗上了。

真难想象再象我引用文章那样的给嵌套的dtatgrid在动态创建列会怎样。