Row already belongs to another table

When copying a row from one datatable to another you might get the error "this row already belongs to another table".
Typically you might write code like this:

string sConnString = ConfigurationManager.ConnectionStrings["NorthwindConn"].ConnectionString; 

DataSet ds = Microsoft.ApplicationBlocks.Data.SqlHelper.ExecuteDataset(sConnString,CommandType.Text, 

"select * from suppliers order by supplierid"); 

int nRowCount = 0;

DataTable dt = ds.Tables[0];DataTable dt2 = dt.Clone();

dt2.Clear();

foreach (DataRow row in dt.Rows)

{ 

dt2.Rows.Add(row);

nRowCount++;

if (nRowCount == 10)

{

DataRow rowNew = dt2.NewRow();

rowNew["supplierid"] = -12345;

dt2.Rows.Add(rowNew);

nRowCount = 0;

}

} 

The correct way is instead to "import" the row using ImportRow

string sConnString = ConfigurationManager.ConnectionStrings["NorthwindConn"].ConnectionString;

DataSet ds = Microsoft.ApplicationBlocks.Data.SqlHelper.ExecuteDataset(sConnString,CommandType.Text,

"select * from suppliers order by supplierid"); 

int nRowCount = 0; 

DataTable dt = ds.Tables[0]; 

DataTable dt2 = dt.Clone(); 

dt2.Clear(); 

foreach (DataRow row in dt.Rows) 

{ 

dt2.ImportRow(row); 

nRowCount++; 

if (nRowCount == 10) 

{ 

DataRow rowNew = dt2.NewRow(); 

rowNew["supplierid"] = -12345; 

dt2.Rows.Add(rowNew); 

nRowCount = 0; 

} 

}