using System;

using System.Collections.Generic;

using System.Data;

using System.Linq;

namespace DTS

{

    class Program

    {

        static void Main(string[] args)

        {

            DataTable _dt = new DataTable();

            _dt.Columns.Add("id", typeof(int));

            _dt.Columns.Add("name", typeof(string));

            _dt.Columns.Add("address", typeof(string));

            DataRow _dr = _dt.NewRow();

            _dr["id"] = ;

            _dr["name"] = "xiaodong";

            _dr["address"] = "beijing";

            _dt.Rows.Add(_dr);

            _dt.Rows.Add(_dr.ItemArray);

            _dt.Rows.Add(_dr.ItemArray);

            _dr = _dt.NewRow();

            _dr["id"] = ;

            _dr["name"] = "xiaodong";

            _dr["address"] = "shanghai";

            _dt.Rows.Add(_dr);

            _dr = _dt.NewRow();

            _dr["id"] = ;

            _dr["name"] = "xiaoming";

            _dr["address"] = "guangdong";

            _dt.Rows.Add(_dr);

            _dr = _dt.NewRow();

            _dr["id"] = ;

            _dr["name"] = "xudaxia";

            _dr["address"] = "fujian";

            _dt.Rows.Add(_dr);

            _dt.Rows.Add(_dr.ItemArray);

            Console.WriteLine("--------------------原来有重复数据的Table----------------------");

            _dt.AsEnumerable().ToList().ForEach(

                m=>

                {

                    Console.WriteLine(m["id"].ToString() + "   " + m["name"].ToString() + "  " + m["address"].ToString());

                });

            Console.WriteLine("--------------------去除重复后的Table----------------------");

            var _comPresult = _dt.AsEnumerable().Distinct(new DataTableRowCompare());

            DataTable _resultDt = _comPresult.CopyToDataTable();

            _resultDt.AsEnumerable().ToList().ForEach(

               x =>

               {

                   Console.WriteLine(x["id"].ToString() + "    " + x["name"].ToString() + "   " + x["address"].ToString());

               });

            Console.Read();

        }

        public class DataTableRowCompare : IEqualityComparer<DataRow>

        {

            #region IEqualityComparer<DataRow> 成员

            public bool Equals(DataRow x, DataRow y)

            {

                return ((x.Field<int>("id") == y.Field<int>("id") && x.Field<string>("name") == y.Field<string>("name") && x.Field<string>("address") == y.Field<string>("address")));

            }

            public int GetHashCode(DataRow obj)

            {

                return obj.ToString().GetHashCode();

            }

            #endregion

        }

    }

}

public static DataTable DistinctSomeColumn(DataTable sourceTable, params string[] fieldName)

{

    if (fieldName == null || fieldName.Length == ) return sourceTable;

    return sourceTable.AsEnumerable().Distinct(new ColumnEquals(fieldName)).CopyToDataTable();

}  

public class ColumnEquals : IEqualityComparer<DataRow>

{

    public ColumnEquals(string[] sArr)

    {

        _sArr = sArr;

    }  

    private string[] _sArr;  

    public bool Equals(DataRow x, DataRow y)

    {

        return !_sArr.Any(p => !x[p].Equals(y[p]));

    }  

    public int GetHashCode(DataRow dr)

    {

        return dr.ToString().GetHashCode();

    }

}