DataSet 添加数据集、行、列、主键和外键等操作示例

前台代码：html

<% @ Page language="c#" Codebehind="CodeUse.aspx.cs" AutoEventWireup="false" Inherits="DsAndXML.CodeUse"  %>
<! DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"  >
< HTML >
     < HEAD >
         < title > CodeUse </ title >
         < meta  content ="Microsoft Visual Studio 7.0"  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  MS_POSITIONING ="GridLayout" >
         < form  id ="CodeUse"  method ="post"  runat ="server" >
             < FONT  face ="宋体" >
                 < asp:button  id ="btnCreate"  style ="Z-INDEX: 100; LEFT: 31px; POSITION: absolute; TOP: 43px"  runat ="server"  Height ="36"  Width ="130"  Text ="创建数据集和数据表" ></ asp:button >
                 < asp:Button  id ="btnUpdateDs"  style ="Z-INDEX: 117; LEFT: 35px; POSITION: absolute; TOP: 439px"  runat ="server"  Height ="36px"  Width ="131px"  Text ="赋值" ></ asp:Button >
                 < asp:Label  id ="Label3"  style ="Z-INDEX: 112; LEFT: 352px; POSITION: absolute; TOP: 395px"  runat ="server" > 列号: </ asp:Label >
                 < asp:Label  id ="Label2"  style ="Z-INDEX: 111; LEFT: 209px; POSITION: absolute; TOP: 395px"  runat ="server" > 行号： </ asp:Label >
                 < asp:Button  id ="btnUpdateMID"  style ="Z-INDEX: 107; LEFT: 37px; POSITION: absolute; TOP: 330px"  runat ="server"  Height ="36"  Width ="131"  Text ="修改MasterID" ></ asp:Button >
                 < asp:Button  id ="btnAddForeign"  style ="Z-INDEX: 106; LEFT: 35px; POSITION: absolute; TOP: 278px"  runat ="server"  Height ="36"  Width ="131"  Text ="添加外键" ></ asp:Button >
                 < asp:Button  id ="Button1"  style ="Z-INDEX: 105; LEFT: 31px; POSITION: absolute; TOP: 217px"  runat ="server"  Height ="36px"  Width ="130px"  Text ="添加唯一键" ></ asp:Button >< asp:button  id ="btnAddRow"  style ="Z-INDEX: 102; LEFT: 31px; POSITION: absolute; TOP: 161px"  runat ="server"  Height ="36px"  Width ="130px"  Text ="添加行" ></ asp:button >< asp:button  id ="btnAddColumn"  style ="Z-INDEX: 101; LEFT: 31px; POSITION: absolute; TOP: 102px"  runat ="server"  Height ="36px"  Width ="130px"  Text ="添加列" ></ asp:button >< asp:datagrid  id ="dgMaster"  style ="Z-INDEX: 103; LEFT: 242px; POSITION: absolute; TOP: 40px"  runat ="server"  Height ="120px"  Width ="485px" ></ asp:datagrid >< asp:datagrid  id ="dgChild"  style ="Z-INDEX: 104; LEFT: 240px; POSITION: absolute; TOP: 193px"  runat ="server"  Height ="111px"  Width ="479px" ></ asp:datagrid >
                 < asp:TextBox  id ="tbRow"  style ="Z-INDEX: 108; LEFT: 275px; POSITION: absolute; TOP: 395px"  runat ="server"  Width ="54px" ></ asp:TextBox >
                 < asp:TextBox  id ="tbCol"  style ="Z-INDEX: 109; LEFT: 422px; POSITION: absolute; TOP: 395px"  runat ="server"  Width ="64px" ></ asp:TextBox >
                 < asp:Label  id ="Label1"  style ="Z-INDEX: 110; LEFT: 520px; POSITION: absolute; TOP: 399px"  runat ="server" > 值： </ asp:Label >
                 < asp:TextBox  id ="tbResult"  style ="Z-INDEX: 113; LEFT: 585px; POSITION: absolute; TOP: 394px"  runat ="server"  Width ="145px" ></ asp:TextBox >
                 < asp:Label  id ="Label4"  style ="Z-INDEX: 114; LEFT: 209px; POSITION: absolute; TOP: 344px"  runat ="server" > 表： </ asp:Label >
                 < asp:DropDownList  id ="ddlTable"  style ="Z-INDEX: 115; LEFT: 277px; POSITION: absolute; TOP: 341px"  runat ="server" >
                     < asp:ListItem  Value ="0" > 表一 </ asp:ListItem >
                     < asp:ListItem  Value ="1" > 表二 </ asp:ListItem >
                 </ asp:DropDownList >
                 < asp:Button  id ="Button2"  style ="Z-INDEX: 116; LEFT: 35px; POSITION: absolute; TOP: 389px"  runat ="server"  Height ="36px"  Width ="131px"  Text ="求值" ></ asp:Button ></ FONT ></ form >
     </ body >
</ HTML >

后台代码：cs

using  System;
using  System.Collections;
using  System.ComponentModel;
using  System.Data;
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  DsAndXML
{
    /**//// <summary>
    /// CodeUse 的摘要说明。
    /// </summary>
    public class CodeUse : System.Web.UI.Page
    {
        protected System.Web.UI.WebControls.Button btnAddColumn;
        protected System.Web.UI.WebControls.Button btnAddRow;
        protected System.Web.UI.WebControls.DataGrid dgMaster;
        protected System.Web.UI.WebControls.DataGrid dgChild;
        protected System.Web.UI.WebControls.Button Button1;
        protected System.Web.UI.WebControls.Button btnAddForeign;
        protected System.Web.UI.WebControls.Button btnUpdateMID;
        protected System.Web.UI.WebControls.TextBox tbRow;
        protected System.Web.UI.WebControls.TextBox tbCol;
        protected System.Web.UI.WebControls.Label Label1;
        protected System.Web.UI.WebControls.Label Label2;
        protected System.Web.UI.WebControls.Label Label3;
        protected System.Web.UI.WebControls.TextBox tbResult;
        protected System.Web.UI.WebControls.Label Label4;
        protected System.Web.UI.WebControls.DropDownList ddlTable;
        protected System.Web.UI.WebControls.Button Button2;
        protected System.Web.UI.WebControls.Button btnUpdateDs;
        protected System.Web.UI.WebControls.Button btnCreate;
    
        private void Page_Load(object sender, System.EventArgs e)
        {
            // 在此处放置用户代码以初始化页面
        }

        Web Form Designer generated code#region Web Form Designer generated code
        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.btnCreate.Click += new System.EventHandler(this.btnCreate_Click);
            this.btnAddRow.Click += new System.EventHandler(this.btnAddRow_Click);
            this.btnAddColumn.Click += new System.EventHandler(this.btnAddColumn_Click);
            this.Button1.Click += new System.EventHandler(this.Button1_Click);
            this.btnAddForeign.Click += new System.EventHandler(this.btnAddForeign_Click);
            this.btnUpdateMID.Click += new System.EventHandler(this.btnUpdateMID_Click);
            this.Button2.Click += new System.EventHandler(this.Button2_Click);
            this.btnUpdateDs.Click += new System.EventHandler(this.btnUpdateDs_Click);
            this.Load += new System.EventHandler(this.Page_Load);

        }
        #endregion

        private void btnCreate_Click(object sender, System.EventArgs e)
        {
            DataSet dsUntyped = new DataSet("myDS");//创建数据集
            DataTable dtMaster = new DataTable("Master");//创建数据表
            DataTable dtChild = new DataTable("Child");
            dsUntyped.Tables.Add(dtMaster);//把数据表添加到数据集中
            dsUntyped.Tables.Add(dtChild);
            Session["ds"] = dsUntyped;
            
        }

        private void btnAddColumn_Click(object sender, System.EventArgs e)
        {
            DataSet dsUntyped = (DataSet)Session["ds"];
            dsUntyped.Tables["Master"].Columns.Add("MasterID",typeof(int));
            dsUntyped.Tables["Master"].Columns.Add("MasterValue",typeof(string));
            dsUntyped.Tables["Child"].Columns.Add("MasterLink",typeof(int));
            dsUntyped.Tables["Child"].Columns.Add("ChildID",typeof(int));
            dsUntyped.Tables["Child"].Columns .Add("ChildValue",typeof(string));
            //修改表头
            dsUntyped.Tables["Master"].Columns["MasterID"].Caption = "主ID";
            dsUntyped.Tables["Master"].Columns["MasterValue"].Caption = "值";
            Session["ds"] = dsUntyped;
            Bind();
        }

        private void btnAddRow_Click(object sender, System.EventArgs e)
        {
            try
            {
                DataSet dsUntyped = (DataSet)Session["ds"];
                //为Master表添加两行
                DataRow dr = dsUntyped.Tables["Master"].NewRow();
                dr["MasterID"] = 1;
                dr["MasterValue"] = "One";
                dsUntyped.Tables["Master"].Rows.Add(dr);
                dr = dsUntyped.Tables["Master"].NewRow();
                dr["MasterID"] = 2;
                dr["MasterValue"] = "Two";
                dsUntyped.Tables["Master"].Rows.Add(dr);
                //为child表添加1行
                dr = dsUntyped.Tables["Child"].NewRow();
                dr["MasterLink"] = 1;
                dr["ChildID"] = 1;
                dr["ChildValue"] = "ChildOne";
                dsUntyped.Tables["Child"].Rows.Add(dr);
                Session["ds"] = dsUntyped;
                Bind();
            }
            catch(Exception ee)
            {
                Response.Write(ee.Message);
            }
        
        }
        //添加唯一键
        private void Button1_Click(object sender, System.EventArgs e)
        {
            DataSet dsUntyped = (DataSet)Session["ds"];
            System.Data.UniqueConstraint uc = new UniqueConstraint("unqi",dsUntyped.Tables["Master"].Columns["MasterID"]);
            dsUntyped.Tables["Master"].Constraints.Add(uc);
            Session["ds"] = dsUntyped;
        }
        private void Bind()
        {
            DataSet dsUntyped = (DataSet)Session["ds"];
            dgMaster.DataSource = dsUntyped.Tables["Master"].DefaultView;
            dgChild.DataSource = dsUntyped.Tables["Child"].DefaultView;
            this.DataBind();
        }

        private void btnAddForeign_Click(object sender, System.EventArgs e)
        {
            DataSet dsUntyped = (DataSet)Session["ds"];
            System.Data.ForeignKeyConstraint fc = new ForeignKeyConstraint("fc",dsUntyped.Tables["Master"].Columns["MasterID"],dsUntyped.Tables["Child"].Columns["MasterLink"]);
            dsUntyped.Tables["Child"].Constraints.Add(fc);
            Session["ds"] = dsUntyped;

        }

        private void btnUpdateMID_Click(object sender, System.EventArgs e)
        {
            DataSet dsUntyped = (DataSet)Session["ds"];
            dsUntyped.Tables["Master"].Rows[0]["MasterID"] = 4;
            Bind();
        }

        private void Button2_Click(object sender, System.EventArgs e)
        {
            DataSet dsUntyped = (DataSet)Session["ds"];
            int nIndexTb = int.Parse(ddlTable.SelectedItem.Value);
            int nIndexRow = int.Parse(tbRow.Text);
            int nIndexCol = int.Parse(tbCol.Text);
            object obj = dsUntyped.Tables[nIndexTb].Rows[nIndexRow][nIndexCol];
            tbResult.Text = obj.ToString();
            
        }

        private void btnUpdateDs_Click(object sender, System.EventArgs e)
        {
            DataSet dsUntyped = (DataSet)Session["ds"];
            int nIndexTb = int.Parse(ddlTable.SelectedItem.Value);
            int nIndexRow = int.Parse(tbRow.Text);
            int nIndexCol = int.Parse(tbCol.Text);
            dsUntyped.Tables[nIndexTb].Rows[nIndexRow][nIndexCol] = tbResult.Text;
            Session["ds"] = dsUntyped;
            Bind();
        }
    }
}

如何把利用DataSet的GetXml()方法获得的字符串再转成DataSet对象 
DataSet ds  =  db.ExecSqlForDataSet( strSQL );
string  strDS  =  ds.GetXml();

// 如何把strDS转换成DataSet对象??

--------------------------------------------------------------------------------

String strDS  =   " "
System.IO.StringReader reader  =   new  System.IO.StringReader(strDS);
ds.ReadXml(reader);
reader.Close();