C#DataViewRowState一个数据表的数据状态示例

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/*
*模块名称:行状态展示
*实体名称:
*创建者:Fung
*创建时间:
*修改者:
*修改时间:2006-12-18
*说明:本程序为C#2005控制台程序;
 *     演示了数据表内数据变化的各种状态。
*/


using System;
using System.Collections.Generic;
using System.Text;
using System.Data;

namespace DataRowState
{
    
class Program
    
{
        
static void Main(string[] args)
        
{
            DemonstrateRowState();
        }

        
static private void DemonstrateRowState()
        
{
            
// 创建一个仅有一列的空表
            DataTable dataTable = new DataTable("dataTable");
            DataColumn dataColumn 
= new DataColumn("dataColumn");
            dataTable.Columns.Add(dataColumn);

            
// 添加十行记录item 0,item 1,item 2,...,item 9
            DataRow dataRow;
            
for (int i = 0; i < 10; i++)
            
{
                dataRow 
= dataTable.NewRow();
                dataRow[
"dataColumn"= "item " + i;
                dataTable.Rows.Add(dataRow);
            }

            
//标记接收数据变化
            dataTable.AcceptChanges();

            
// 创建数据表视图
            DataView dataView = new DataView(dataTable);

            
// 改变一个行值
            dataTable.Rows[1]["dataColumn"= "Hello";

            
// Add one row:
            dataRow = dataTable.NewRow();
            dataRow[
"dataColumn"= "World";
            dataTable.Rows.Add(dataRow);

            
// 设置行过滤,仅显示新增的和当前改变的
            dataView.RowStateFilter = DataViewRowState.Added
                
| DataViewRowState.ModifiedCurrent;

            
// 输出行为 "Hello" "World"
            PrintView(dataView, "ModifiedCurrent and Added");

            
// 设置过滤显示被修改行的原始值
            dataView.RowStateFilter = DataViewRowState.ModifiedOriginal;
            PrintView(dataView, 
"ModifiedOriginal");

            
// 删除3行
            dataTable.Rows[1].Delete();
            dataTable.Rows[
2].Delete();
            dataTable.Rows[
3].Delete();

            
// 设置行过滤显示只显示和修改 
            dataView.RowStateFilter = DataViewRowState.Deleted;
            PrintView(dataView, 
"Deleted");

            
//显示当前数据
            dataView.RowStateFilter = DataViewRowState.CurrentRows;
            PrintView(dataView, 
"Current");

            
//显示没有改变的行
            dataView.RowStateFilter = DataViewRowState.Unchanged;
            PrintView(dataView, 
"Unchanged");

            
//显示原始数据.
            dataView.RowStateFilter = DataViewRowState.OriginalRows;
            PrintView(dataView, 
"OriginalRows");
        }


        
static private void PrintView(DataView dataView, string label)
        
{
            Console.WriteLine(
" " + label);
            
for (int i = 0; i < dataView.Count; i++)
            
{
                Console.WriteLine(dataView[i][
"dataColumn"]);
            }

        }

    }

}