• DataTable的Merge使用


    using System;
    using System.Collections.Generic;
    using System.Data;
    using System.Linq;
    using System.Text;
    using System.Threading.Tasks;
    
    namespace ConsoleApplication1
    {
        class Program
        {
            private static void PrintValues(DataTable table)
            {
                string label = table.TableName;
                Console.WriteLine("TableName: " + table.TableName);
    
                foreach (DataColumn column in table.Columns)
                {
                    Console.Write("	 " + column.ColumnName);
                }
                Console.WriteLine();
                foreach (DataRow row in table.Rows)
                {
                    foreach (DataColumn column in table.Columns)
                    {
                        Console.Write("	 |{0}|", row[column]);
                    }
                    Console.WriteLine();
                }
            }
            static void Main(string[] args)
            {
                DataTable dtWs = new DataTable("dtWs");
                //DataColumn dcWsWId = new DataColumn("WID", Type.GetType("System.Int32"));//“System.Data.DataException”类型的未经处理的异常在 System.Data.dll 中发生其他信息: < target >.WID 和<source>.WID 擁有衝突的屬性: DataType 屬性不符。
                DataColumn dcWsWId = new DataColumn("WID", Type.GetType("System.String"));
                DataColumn dcWsFId = new DataColumn("FID", Type.GetType("System.String"));
                DataColumn dcBNId = new DataColumn("ADD", Type.GetType("System.String"));
                dtWs.Columns.Add(dcWsWId);
                dtWs.Columns.Add(dcWsFId);
                dtWs.Columns.Add(dcBNId);
                dtWs.PrimaryKey = new DataColumn[] { dcWsWId, dcWsFId };
                for (int i = 0; i < 5; i++)
                {
                    DataRow drNew = dtWs.NewRow();
                    drNew["WID"] = i;
                    drNew["FID"] = "";
                    drNew["ADD"] = "BBBB" + i;
                    dtWs.Rows.Add(drNew);
                }
                PrintValues(dtWs);
    
                DataTable dtQry = new DataTable("dtQry");
                DataColumn dcWId = new DataColumn("WID", Type.GetType("System.String"));
                DataColumn dcFId = new DataColumn("FID", Type.GetType("System.String"));
                DataColumn dcNId = new DataColumn("Name", Type.GetType("System.String"));
                dtQry.Columns.Add(dcWId);
                dtQry.Columns.Add(dcFId);
                dtQry.Columns.Add(dcNId);
                dtQry.PrimaryKey = new DataColumn[] { dcWId, dcFId };
                for (int i = 3; i < 8; i++)
                {
                    DataRow drNew = dtQry.NewRow();
                    drNew["WID"] = i;
                    drNew["FID"] = "";
                    drNew["Name"] = "AAAA" + i;
                    dtQry.Rows.Add(drNew);
                }
                PrintValues(dtQry);
    
                dtQry.Merge(dtWs, true, MissingSchemaAction.AddWithKey);
                PrintValues(dtQry);
    
                dtQry.Merge(dtWs, false, MissingSchemaAction.AddWithKey);
                PrintValues(dtQry);
    
                Console.Read();
            }
        }
    }

    執行結果:

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  • 原文地址:https://www.cnblogs.com/chen110xi/p/6066103.html
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