C# - Drag item out of listview into a trash can?

Question

How do I drag a item out of a Winforms-listview control onto another control (picture of trash can)?

UPDATE1:

I think the basic flow is:

• for the ItemDrag event on the listview have a DoDragDrop
• Then have a DragEnter event on the picturebox that captures that drag?

UPDATE2:

The basic flow (based on answers):

• add 'ItemDrag' event to the listview.
• add a 'DoDragDrop' inside the 'ItemDrag'
• add 'DragEnter' event to the picturebox.
• add a 'GetDataPresent' check inside the 'DragEnter' to check on the data type
• add a 'DragDrop' event to the picturebox
• add a 'GetDataPresent' check inside the 'DragEnter' to check on the data type

Answer 1

EDIT This applies only if you want shell integrated drag-and-drop. If you are not integrating with the shell, and only dragging and dropping between things in your own app, then this answer does not apply. My apologies for the confusion.

---

You need to support drag-n-drop in your app or control. This involves some COM interop.

It seems a little complicated at first, but once you get the basic skeleton up, it's not that hard to implement. Also there's a nice guide right here, that tells you how:

http://blogs.msdn.com/adamroot/pages/shell-style-drag-and-drop-in-net-wpf-and-winforms.aspx

Answer 2

Implement an event handler for the list view's ItemDrag event:

    private void listView1_ItemDrag(object sender, ItemDragEventArgs e) {
        DoDragDrop(e.Item, DragDropEffects.Move);
    }

And write the event handlers for the trash can:

    private void trashCan_DragEnter(object sender, DragEventArgs e) {
        if (e.Data.GetDataPresent(typeof(ListViewItem))) {
            e.Effect = DragDropEffects.Move;
        }
        // others...
    }

    private void trashCan_DragDrop(object sender, DragEventArgs e) {
        if (e.Data.GetDataPresent(typeof(ListViewItem))) {
            var item = e.Data.GetData(typeof(ListViewItem)) as ListViewItem;
            item.ListView.Items.Remove(item);
        }
        // others...
    }

You'll have to force the AllowDrop property for the PictureBox, it isn't available in the Properties window:

    public Form1() {
        InitializeComponent();
        trashCan.AllowDrop = true;
    }

Answer 3

Look into DragEnter, DragLeave, and DragDrop. Also see example, Implementing Drag and Drop in ListView Controls