Export to excel from observablecollection C#

Question

I'm trying to export a WPF datagrid to an Excel sheet, but I keep getting errors. I have found this examples, but I don't know how to export from an observablecollection. In this example it seems that there is a list. So I think I have to cast from list to observablecollection, but I can't get it right. I'm still new to functionality in C# and WPF, so any help is very appreciated.

Export WPF DataGrid to Excel

http://www.codeproject.com/Articles/120480/Export-to-Excel-Functionality-in-WPF-DataGrid

My code

    private ObservableCollection<T_P> _observableCollection;
    private CollectionViewSource _collectionViewSource;

    public ExportExcel()
    {
        InitializeComponent();


        using (var dc = new DataClasses2DataContext())
        {
            _observableCollection = new ObservableCollection<T_P>(dc.T_Ps);
        }

        _collectionViewSource = (CollectionViewSource)this.FindResource("_T_PViewSource") as CollectionViewSource;
        _collectionViewSource.Source = _observableCollection;


        this.T_P = new T_P();
        this.DataContext = T_P;

    }

    private void btnExportExcel_Click(object sender, RoutedEventArgs e)
    {
        ExportToExcel();
       //some code here?  
    }

// How can I call this class?

    public class ExportToExcel<T>
        where T : class
    {
        public List<T> dataToPrint;
        // Excel object references.
        private Excel.Application _excelApp = null;
        private Excel.Workbooks _books = null;
        private Excel._Workbook _book = null;
        private Excel.Sheets _sheets = null;
        private Excel._Worksheet _sheet = null;
        private Excel.Range _range = null;
        private Excel.Font _font = null;
        // Optional argument variable
        private object _optionalValue = Missing.Value;

//......

Answer 1

Your code is incomplete so it's hard to tell, but it goes along these lines:

private void btnExportExcel_Click(object sender, RoutedEventArgs e)
{
    var exporter = new ExportToExcel<T_P>()
    {
       dataToPrint = new List<T_P>(_observableCollection);
    };

}