Copy rows from one Datatable to another DataTable?

I've created an easy way to do this issue

 DataTable newTable = oldtable.Clone();    
 for (int i = 0; i < oldtable.Rows.Count; i++)
 {
   DataRow drNew = newTable.NewRow();    
   drNew.ItemArray = oldtable.Rows[i].ItemArray;    
   newTable.Rows.Add(drNew);   
 } 

I needed to copy rows from multiple tables with the same structure into a new table to be used as a datasource for datagridview:

// Generate DataTable[] alltables from multiple datatables

DataTable newTable = alltables[0].Clone();
foreach (DataTable dt in alltables)
{
   for (int i = 0; i < dt.Rows.Count; i++)
      newTable.Rows.Add(dt.Rows[i].ItemArray);
}

To copy whole datatable just do this:

DataGridView sourceGrid = this.dataGridView1;
DataGridView targetGrid = this.dataGridView2;
targetGrid.DataSource = sourceGrid.DataSource;

For those who want single command SQL query for that:

INSERT INTO TABLE002 
(COL001_MEM_ID, COL002_MEM_NAME, COL002_MEM_ADD, COL002_CREATE_USER_C, COL002_CREATE_S)
SELECT COL001_MEM_ID, COL001_MEM_NAME, COL001_MEM_ADD, COL001_CREATE_USER_C, COL001_CREATE_S
FROM TABLE001;

This query will copy data from TABLE001 to TABLE002 and we assume that both columns had different column names.

Column names are mapped one-to-one like:

COL001_MEM_ID -> COL001_MEM_ID

COL001_MEM_NAME -> COL002_MEM_NAME

COL001_MEM_ADD -> COL002_MEM_ADD

COL001_CREATE_USER_C -> COL002_CREATE_USER_C

COL002_CREATE_S -> COL002_CREATE_S

You can also specify where clause, if you need some condition.

There is better way to do this.

DataTable targetDataTable = new DataTable(); targetDataTable = changedColumnMetadata.AsEnumerable().Where(dataRow => entityName.Equals(dataRow["EntityName"])).CopyToDataTable();

Please try this and let me know in case of any issues.

You can do it calling the DataTable.Copy() method, for example:

   DataSet ds = new DataSet();
   System.Data.DataTable dt = new System.Data.DataTable();
   dt = _BOSearchView.DS.Tables[BusLib.TPV.TableName.SearchView].Copy();
   ds.Tables.Add(dt);
   UltGrdSaleExcel.SetDataBinding(ds, dt.TableName, true);

use Merge, this will append all rows of newDataTable with oldDateTale

oldDateTale.Merge(newDataTable);