Question

I have a DataTable which has some rows and I am using the select to filter the rows to get a collection of DataRows which I then loop through using foreach and add it to another DataTable, but it is giving me the error ‘This Row already belongs to another table’. Here is the code:

DataTable dt = (DataTable)Session['dtAllOrders']; DataTable dtSpecificOrders = new DataTable();  DataRow[] orderRows = dt.Select('CustomerID = 2');  foreach (DataRow dr in orderRows) {     dtSpecificOrders.Rows.Add(dr); //Error thrown here. } 

Answer 1

You need to create a new Row with the values from dr first. A DataRow can only belong to a single DataTable.

You can also use Add which takes an array of values:

myTable.Rows.Add(dr.ItemArray) 

Or probably even better:

// This works because the row was added to the original table. myTable.ImportRow(dr);  // The following won't work. No data will be added or exception thrown. var drFail = dt.NewRow() drFail['CustomerID'] = '[Your data here]'; // dt.Rows.Add(row); // Uncomment for import to succeed. myTable.ImportRow(drFail);