Need to add new row in data grid of WPF with specific data, each time for click button

Question

i want to add a new row in data grid of WPF with specific data each time I click a button, where rows will be one after another.However my code is just replacing the previous on not adding a new one below it: here is my code behind:

        ObservableCollection<DataItem> items = new ObservableCollection<DataItem>();
        items.Add(new DataItem() { Product = product, Quantity =       qnt.ToString(), Price = price, Total = totalPrice.ToString() });

        dataGrid.ItemsSource = items;

"dataGrid" is the name in the XAML. Can anyone help!

Answer 1

There is no need to bind the Datagrid to an observable collection. If you want to do so, then please have a look at MVVM pattern for WPF. If you just want to add a row to the datagrid, use this code :

DataGrid.Items.Add(new DataItem() { Product = product, Quantity =       qnt.ToString(), Price = price, Total = totalPrice.ToString() });

Also consider adding a datatable as the source by checking out this answer.

Answer 2

Create the ObservableCollection and set the ItemSource property of the DataGrid once, for example in the constructor of your window or user control. Make sure that you store a reference to the ObservableCollection in the class:

public partial class MainWindow : Window
{
    ObservableCollection<DataItem> items = new ObservableCollection<DataItem>();
    public MainWindow()
    {
        InitializeComponent();

        items.Add(new DataItem() { Product = product, Quantity = qnt.ToString(), Price = price, Total = totalPrice.ToString() });
        dataGrid.ItemsSource = items;
    }
}

You will then able able to add new items to the same ObservableCollection from any other method of class including your Click event handler:

private void Button_Click(object sender, RoutedEventArgs e)
{
    items.Add(new DataItem() { Product = product, Quantity = qnt.ToString(), Price = price, Total = totalPrice.ToString() });
}