两个DataTable合并

小鱼儿 2022-02-26 01:40 276阅读 0赞

看到CSDN朋友不断提问关于合并DataTable的问题（虽然DataTable.Merge可以很好的实现）。为了大家更好的改造或者理解，抽空简单写了几行代码，共享大家

两个结构一样的DataTable合并

DataTable DataTable1 = new DataTable(); 
    DataTable DataTable2 = new DataTable(); 
    DataTable newDataTable = DataTable1.Clone(); 
    
    object[] obj = new object[newDataTable.Columns.Count]; 
    for (int i = 0; i < DataTable1.Rows.Count; i++) 
    { 
        DataTable1.Rows[i].ItemArray.CopyTo(obj,0); 
        newDataTable.Rows.Add(obj); 
    } 
    for (int i = 0; i < DataTable2.Rows.Count; i++) 
    { 
        DataTable2.Rows[i].ItemArray.CopyTo(obj,0); 
        newDataTable.Rows.Add(obj); 
    }
    //或者
    DataTable DataTable1 = new DataTable(); 
    DataTable DataTable2 = new DataTable(); 
    
    object[] obj = new object[DataTable1 .Columns.Count]; 
    for (int i = 0; i < DataTable2.Rows.Count; i++) 
    { 
        DataTable2.Rows[i].ItemArray.CopyTo(obj,0); 
        DataTable1.Rows.Add(obj); 
    }
    //或者
    //DataTable2
    DataTable dt2 = ds.Tables["dt2"];
    //将DataTable2中的行添加到DataTable1
    //前提：dt1和dt2表结构相同
    foreach (DataRow dr in dt2.Rows)
          dt1.Rows.Add(dr.ItemArray);

两个结构不同的DataTable合并

/// <summary> 
      /// 将两个列不同的DataTable合并成一个新的DataTable 
      /// </summary> 
      /// <param name="dt1">Table表1</param> 
      /// <param name="dt2">Table表2</param> 
      /// <param name="DTName">合并后新的表名</param> 
      /// <returns></returns>
    
      private DataTable UniteDataTable( DataTable dt1 ,DataTable dt2 ,string DTName) 
      {  
       DataTable dt3 = dt1.Clone(); 
       for( int i = 0 ;i < dt2.Columns.Count ;i ++ ) 
       { 
        dt3.Columns.Add( dt2.Columns[i].ColumnName ) ; 
       } 
       object[] obj = new object[dt3.Columns.Count]; 
        
       for (int i = 0; i < dt1.Rows.Count; i++) 
       { 
        dt1.Rows[i].ItemArray.CopyTo(obj,0); 
        dt3.Rows.Add(obj); 
       } 
           
       if( dt1.Rows.Count >= dt2.Rows.Count ) 
       { 
        for( int i = 0 ;i < dt2.Rows.Count ;i++ ) 
        { 
         for( int j = 0 ;j < dt2.Columns.Count ;j ++ ) 
         { 
          dt3.Rows[i][j+dt1.Columns.Count] = dt2.Rows[i][j].ToString() ; 
         } 
        } 
       } 
       else 
       { 
        DataRow dr3 ; 
        for( int i = 0 ;i < dt2.Rows.Count - dt1.Rows.Count ;i ++ ) 
        { 
         dr3 = dt3.NewRow() ; 
         dt3.Rows.Add( dr3 ) ; 
        } 
        for( int i = 0 ;i < dt2.Rows.Count ;i++ ) 
        { 
         for( int j = 0 ;j < dt2.Columns.Count ;j ++ ) 
         { 
          dt3.Rows[i][j+dt1.Columns.Count] = dt2.Rows[i][j].ToString() ; 
         } 
        } 
       } 
       dt3.TableName = DTName ; 
       return dt3 ; 
      }

原文地址：http://blog.csdn.net/gisfarmer/article/details/3900023