How to copy data rows from one DataTable to another

DataTable dt = "";  Here is the DataTable data that fills the datatable dtnew = dt. Copy ();  Copy DT table data structure dtnew.clear (  )<  DT. Rows.Count; i++)        {            if (conditional statement)            {                dtNew.Rows.Add (dt. Rows[i]. ItemArray);  Add data row            }        }

= = = Premise: We already have a DataTable of data that is needed just one row of data = = =

For example, the following code returns a datatable! in a method.

             Sqlcon =new SqlConnection (strcon);             sqlcom =new SqlCommand ();             Sqlcom.connection = Sqlcon;             Sqlcom.commandtext = "Select_v";             Sqlcom.commandtype = CommandType.StoredProcedure;             Sqlcon.open ();             SDR = Sqlcom.executereader ();             DT =new DataTable ();             Dt. Load (SDR);

If the returned DataTable is DT,
Method One: Directly copy a DataTable, and then empty the data (column structure is also retained), and finally use the ImportRow () method to add the required row from the DT;

            DataTable DT2 = new DataTable ();            DT2 = dt. Copy ();            DT2. Rows.clear ();            DT2. ImportRow (dt. Rows[0]);//This is the first line to join.

Method Two:

First the new DataTable must include the corresponding column name (column)
An empty, unstructured DataTable is not allowed to add a line directly to it!

             < DT . Columns.count; i++)             {                 DT2. Columns.Add (dt. Columns[i]. ColumnName);//There are overloaded methods that can be added to the type of column data             }

Then you can join the row directly!

1             DataRow DRQ = dt2. NewRow ();             Drq. ItemArray = dt. Rows[0]. itemarray;//This is the first line of DT2 to join             . Rows.Add (DRQ);//2             DT2. ImportRow (dt. Rows[0]);//This is the first line to join.

Finally, you can put the new DataTable in the dataset:
ds = new DataSet ();
Ds. Tables.add (DT2);

Simple way to filter rows of a DataTable by repeating rows

DataView view = table. DefaultView;
DataTable tagettable= view. ToTable (True, "Column1", "Column2", ...);

The source program comes from resources on the network and I record it for later use. may be useful to everyone//table Datatablesource get data string ConnectionString = "Provider=Microsoft.Jet.OLEDB.4.0;            Persist Security Info = False; "+" Data Source = D:\\vb60\\mdb\\northwind.mdb ";              OleDbConnection Conn = new OleDbConnection (ConnectionString);           Conn.Open ();              OleDbDataAdapter Ada = new OleDbDataAdapter ("SELECT * from Orders", Conn);           DataTable Datatablesource = new DataTable ();           Ada.fill (Datatablesource); DataGrid1.DataSource = Datatablesource; Create a new table datatabledest datatable datatabledest = new DataTable (); Copy the structure of the table Datatablesource to the new table datatabledest datatabledest = Datatablesource.clone (); Then copy the data to the new table in the foreach (DataRow dr in Datatablesource.rows) {//using the ImportRow () method to copy the data.            If you use DATATABLEDEST.ROWS.ADD (DR), you will get an error: System.ArgumentException: The row already belongs to another table.           Datatabledest.importrow (DR);  } Datagrid2.datasource = Datatabledest;         Conn.close (); 

How to copy data rows from one DataTable to another