DataSet架构测试

/*--===------------------------------------------===---
DataSet架构测试
            许明会    2007年12月13日 20:57:46
--===------------------------------------------===---*/
using System;
using System.Data;
using System.Data.SqlClient;

namespace xumh
{
    public class runMyApp
    {
        static void Main()
        {
            //准备DataSet和DataTable对象，并建立关联
            DataSet ds = new DataSet();
            DataTable dtMaster = new DataTable("Master");
            DataTable dtChild = new DataTable("Child");
            ds.Tables.Add(dtMaster);
            ds.Tables.Add(dtChild);
            //为DataTable添加Columns
            dtMaster.Columns.Add("MasterID",typeof(int));
            dtMaster.Columns.Add("MasterValue",typeof(string));
            dtChild.Columns.Add("MasterLink",typeof(int));
            dtChild.Columns.Add("ChildID",typeof(int));
            dtChild.Columns.Add("ChildValue",typeof(string));
            //修改DataTable的表头Caption
            //dtMaster.Columns["MasterID"].Caption = "主ID";
            //dtChild.Columns["MasterValue"].Caption="值";
            //return;
            //添加新行
            DataRow dr = dtMaster.NewRow(); //NewRow 方法
            dr["MasterID"] = 1;
            dr["MasterValue"] = "主表字段1";
            dtMaster.Rows.Add(dr);
            dr = dtMaster.NewRow();
            dr["MasterID"] = 2;
            dr["MasterValue"] = "主表字段2";
            dtMaster.Rows.Add(dr);
            //-----
            dr = dtChild.NewRow();
            dr["MasterLink"] = 1 ;
            dr["ChildID"] = 1 ;
            dr["ChildValue"] = "子表字段1";
            dtChild.Rows.Add(dr);
            //添加唯一键
            System.Data.UniqueConstraint uc = 
                new UniqueConstraint("uc_MasterID",dtMaster.Columns["MasterID"]);
            dtMaster.Constraints.Add(uc);
            //添加外键
            System.Data.ForeignKeyConstraint fc = 
                new ForeignKeyConstraint("fc_MasterID",
                    dtMaster.Columns["MasterID"],dtChild.Columns["MasterLink"]);
            dtChild.Constraints.Add(fc); //dtChild,ForeignKey Constraint
            //取值
            foreach(DataRow drow in dtMaster.Rows)
                Console.WriteLine("{0}\t{1}",drow["MasterID"],drow["MasterValue"]);
            //赋值,修改Master表的MasterID，导致Child表的MasterLink随之改变（外键约束）
            dtMaster.Rows[0]["MasterID"] = 3;
            foreach(DataRow drow in dtChild.Rows)
                Console.WriteLine("{0}\t{1}\t{2}",drow["MasterLink"],drow["ChildID"],drow["ChildValue"]);
            //对DataSet进行遍历
            foreach(DataTable dt in ds.Tables)
            {
                foreach(DataRow dataRow in dt.Rows)
                {    
                    for(int i=0; i<dt.Columns.Count; i++)
                        Console.Write("{0}\t",dr[i]);
                    Console.WriteLine();
                }
                Console.WriteLine("----------------");
            }        
        }
    };
}