protected void OnDragOver(object sender, DragEventArgs e)
{
if (!this.textArea.Focused)
{
this.textArea.Focus();
}
Point client = this.textArea.PointToClient(new Point(e.X, e.Y));
if (!this.textArea.TextView.DrawingPosition.Contains(client.X, client.Y))
{
e.Effect = DragDropEffects.None;
return;
}
TextView textView = this.textArea.TextView;
int x = client.X - this.textArea.TextView.DrawingPosition.X;
int y = client.Y;
Rectangle drawingPosition = this.textArea.TextView.DrawingPosition;
TextLocation logicalPosition = textView.GetLogicalPosition(x, y - drawingPosition.Y);
int num = Math.Min(this.textArea.Document.TotalNumberOfLines - 1, Math.Max(0, logicalPosition.Y));
this.textArea.Caret.Position = new TextLocation(logicalPosition.X, num);
this.textArea.SetDesiredColumn();
if (!e.Data.GetDataPresent(typeof(string)) || this.textArea.IsReadOnly(this.textArea.Caret.Offset))
{
e.Effect = DragDropEffects.None;
return;
}
e.Effect = TextAreaDragDropHandler.GetDragDropEffect(e);
}
protected void OnDragEnter(object sender, DragEventArgs e)
{
if (e.Data.GetDataPresent(typeof(string)))
{
e.Effect = TextAreaDragDropHandler.GetDragDropEffect(e);
}
}
public void Attach(TextArea textArea)
{
this.textArea = textArea;
textArea.AllowDrop = true;
textArea.DragEnter += TextAreaDragDropHandler.MakeDragEventHandler(new DragEventHandler(this.OnDragEnter));
textArea.DragDrop += TextAreaDragDropHandler.MakeDragEventHandler(new DragEventHandler(this.OnDragDrop));
textArea.DragOver += TextAreaDragDropHandler.MakeDragEventHandler(new DragEventHandler(this.OnDragOver));
}
private static DragEventHandler MakeDragEventHandler(DragEventHandler h)
{
return((object sender, DragEventArgs e) => {
try
{
h(sender, e);
}
catch (Exception exception)
{
TextAreaDragDropHandler.OnDragDropException(exception);
}
});
}
protected void OnDragDrop(object sender, DragEventArgs e)
{
this.textArea.PointToClient(new Point(e.X, e.Y));
if (e.Data.GetDataPresent(typeof(string)))
{
this.textArea.BeginUpdate();
this.textArea.Document.UndoStack.StartUndoGroup();
try
{
int offset = this.textArea.Caret.Offset;
if (!this.textArea.IsReadOnly(offset))
{
if (e.Data.GetDataPresent(typeof(DefaultSelection)))
{
ISelection data = (ISelection)e.Data.GetData(typeof(DefaultSelection));
if (data.ContainsPosition(this.textArea.Caret.Position))
{
return;
}
else if (TextAreaDragDropHandler.GetDragDropEffect(e) == DragDropEffects.Move)
{
if (!SelectionManager.SelectionIsReadOnly(this.textArea.Document, data))
{
int length = data.Length;
this.textArea.Document.Remove(data.Offset, length);
if (data.Offset < offset)
{
offset -= length;
}
}
else
{
return;
}
}
}
this.textArea.SelectionManager.ClearSelection();
this.InsertString(offset, (string)e.Data.GetData(typeof(string)));
this.textArea.Document.RequestUpdate(new TextAreaUpdate(TextAreaUpdateType.WholeTextArea));
}
}
finally
{
this.textArea.Document.UndoStack.EndUndoGroup();
this.textArea.EndUpdate();
}
}
}