WPF datagrid simple problem

I have开发者_Go百科 a WPF DataGrid with a data source of DataTable. This DataGrid has just one column that is not ReadOnly where the user must enter data. How i can get values?

This is how i bind the data to the grid.

ConstructTable();

foreach (CheckOutData col in _CheckOutCollection)
{
    decimal paidMoney = 0;
    if (col.PaidMoney <= 0)
    {
        paidMoney = 0;
    }
    else
    {
        paidMoney = col.PaidMoney;
    }
    dt.Rows.Add(
        col.ID.ToString(),
        col.RoomType.ToString(),
        col.RoomNumber.ToString(),
        col.RoomPriceWithCurrency.ToString(),
        col.Discount.ToString(),
        col.DiscountedPriceWithCurrency.ToString(),
        col.CheckIn.ToString(),
        col.CheckOut.ToString(),
        col.TotalDay.ToString(),
        col.TotalPrice.ToString(),
        col.IncFirstDay.ToString(),
        paidMoney.ToString());

    _CheckInsIDs.Add(col.ID);
}

dataGrid1.DataContext = ds.Tables[0];

I'm selecting data from an SQL Table int a Collection col. As above, this Collection is used to populate the DataTable. i dont use more this _CheckOutCollection

You need to use two way mode in your datagrid column binding like below :

Binding="{Binding ColName, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"