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How to use Not In datatable.select

I have a DataTable (Ado.Net) with column 'Status'. This column holds the values (in each records)
['Red','Green','Blue','Yellow','White','OtherColors']
I want to select all the rows which status value not Red,Green,Blue
What the kind of filter expression to use to select data with my proposed criteria. So i want to achive some thing like we used in sql query ( WHERE Status NOT IN ('Red','Green','Blue')
NB:This project is running .NET 2.0 i cant use linq

I have tested it, it works as desired:
DataRow[] filtered = tblStatus.Select("Status NOT IN ('Red','Green','Blue')");
The resulting DataRow[] contains only DataRows with OtherColors, Yellow and White.
If you could use LINQ i'd prefer that:
string[] excludeStatus = {"Red","Green","Blue"};
var filteredRows = tblStatus.AsEnumerable()
.Where(row => !excludeStatus.Contains(row.Field<string>("Status")));

Without Linq you can use the rowfilter of a DataView like this
public DataTable GetFilteredData(DataTable table, string[] filterValues)
{
var dv = new DataView(table);
var filter = string.join("','", filterValues);
dv.RowFilter = "Status NOT IN ('" + filter + "')";
return dv.ToTable();
}

Supposing your datatable is part of a typed dataset you can use Linq to datasets, from which you could something like:
var records =
from record in datatable
where !record.Status.Contains('Red','Green','Blue')
select record;
Even if you don't have a typed dataset Linq to datasets is your answer. You would need to some casting, but not to difficult.

sorting a data-table before adding into dataset

I have a dataset that i need to add into a dataset. I need to sort datatable before adding it into dataset.I can use DataView to sort the datatable but cannot figure out how to add this dataview into the dataset. Any ideas
DataView myDataView = MyDataTable.DefaultView;
myDataView.Sort = " Key1, Key2"
MyDataSet.Tables.Add(myDataView); // no overload that takes a dataview

You can create a DataTable by calling DataView.ToTable.

How do I swap TableAdapter DataViews?

I want a user to have different "views" of a TableAdapter. These do not need to be committed back to the database.
I have tried something like the following
mytba.DataView = someOtherDataView;
with no success.
Is it possible to do this?

You need to create a new DataView from the underlying DataTable.
It's been a while since I used TableAdapters, but you can fill a data table with it
DataTable dt = new DataTable();
MyTableAdapter.Fill(dt);
DataView dv1 = new DataView(dt);
DataView dv2 = new DataView(dt);

How to pass DataTable.Select() result to a new DataTable?

I have a DataTable named dt2 with data. I am calling its Select method to get some specific rows.
DataRow[] foundRows;
expression = "parent_id=1";
foundRows = dt2.Select(expression);
How can I pass the Select-method result to a new DataTable – say FilteredData?

You can use CopyToDataTable, available on IEnumerable<DataRow> types.
var filteredData = dt2.Select(expression).CopyToDataTable();

Just for clarity, the Select method returns an array of type DataRow. That's why we need to use CopyToDataTable(). Alex's answer is good. However, if the Select didn't return any rows, CopyToDataTable() will throw an InvalidOperationException.
So test that there is at least one DataRow before using the CopyToDataTable().
var filteredDataRows = dt2.Select(expression);
var filteredDataTable = new DataTable();
if(filteredDataRows.Length != 0)
filteredDataTable = filteredDataRows.CopyToDataTable();

Why not use a DataView instead?
DataView view = new DataView(dt2);
view.RowFilter = "parent_id = 1";
DataView will behave in very much the same way that a DataTable would with the added benefit that any change(s) to the underlying DataTable (dt2 in this case) would be automatically reflected in the DataView.

How do I limit the number of rows in a datatable?

I generate a DataTable (from non-SQL data) and then use a DataView to filter the records.
I want to limit the number of records in the final record set but can't do this when I generate the DataTable.
I've resorted to deleting rows from the final result set, as per:
DataView dataView = new DataView(dataTable);
dataView.RowFilter = String.Format("EventDate > '{0}'", DateTime.Now);
dataView.Sort = "EventDate";
dataTable = dataView.ToTable();
while (dataTable.Rows.Count > _rowLimit)
dataTable.Rows[dataTable.Rows.Count - 1].Delete();
return dataTable;
Is there a more efficient way to limit the results?

You can use Linq:
Try changing your code to the following:
DataView dataView = new DataView(dataTable);
dataView.RowFilter = String.Format("EventDate > '{0}'", DateTime.Now);
dataView.Sort = "EventDate";
dataTable = dataView.ToTable();
while (dataTable.Rows.Count > _rowLimit)
{
dataTable = dataTable.AsEnumerable().Skip(0).Take(50).CopyToDataTable();
}
return dataTable;
You'll need namespace: System.Linq and System.Data

Can you add a column which will be similar like rowcount 1,2,3
Something like incrementing as you add rows from your Non-SQL data to the datatable.
Probably after that you can use
DataRow[] rows1 = dTable.Select(" RowIncrement < 50", "EventDate ASC");
RowIncrement is the column which would be something like ROWNUM

Try copying the top x rows from one datatable into a new one.
dataTable.AsEnumerable().Take(50).CopyToDataTable(newdataTable)
and then use that.