Drag and Drop on a DataGridView

Here is a bit of sample code that allows you to drag and drop a cellvalue in a DataGridView (don’t forget to set the AllowDrop property of the DataGridView to true). Notice that you need to translate the X and Y properties of the DragEventArgs first (unlike the X and Y properties of the MouseEventArgs):

private void dataGridView1_MouseDown( object sender, MouseEventArgs e )
{
 DataGridView.HitTestInfo info = this.dataGridView1.HitTest( e.X, e.Y );
 if ( info.RowIndex != -1 && info.ColumnIndex != -1 )
 {
  Object value = this.dataGridView1.Rows[info.RowIndex].Cells[info.ColumnIndex].Value;
  if (  value != null )
  {
   this.dataGridView1.Rows[info.RowIndex].Cells[info.ColumnIndex].Value = null;
   this.DoDragDrop( value, DragDropEffects.Move );
  }
 }
}

private void dataGridView1_DragDrop( object sender, DragEventArgs e )
{
 Point p = this.dataGridView1.PointToClient( new Point( e.X, e.Y ) );
 DataGridView.HitTestInfo info = this.dataGridView1.HitTest( p.X, p.Y );
 if ( info.RowIndex != -1 && info.ColumnIndex != -1 )
 {
  Object value = (Object)e.Data.GetData( typeof( string ) );
  this.dataGridView1.Rows[info.RowIndex].Cells[info.ColumnIndex].Value = value;
 }
}

private void dataGridView1_DragEnter( object sender, DragEventArgs e )
{
 e.Effect = DragDropEffects.Move;
}