Question

I have a datagrid which is populated with CSV data when the user drag/drops a file onto it. Is it possible to display a message in the blank grid for example ‘Please drag a file here’ or ‘This grid is currently empty’. The grid currently displays as a dark grey box as I wait until the file is dragged to setup the columns etc.

Answer 1

We subclassed the DataGridView control and added this. We didnt need the drag/drop functionality – we just needed to tell the user when there was no data returned from their query.

We have an emptyText property declared like this:

    private string cvstrEmptyText = '';     [Category('Custom')]     [Description('Displays a message in the DataGridView when no records are displayed in it.')]     [DefaultValue(typeof(string), '')]     public string EmptyText     {         get         {             return this.cvstrEmptyText;         }         set         {             this.cvstrEmptyText = value;         }     } 

and overloaded the PaintBackground function:

    protected override void PaintBackground(Graphics graphics, Rectangle clipBounds, Rectangle gridBounds)     {         RectangleF ef;         base.PaintBackground(graphics, clipBounds, gridBounds);         if ((this.Enabled && (this.RowCount == 0)) && (this.EmptyText.Length > 0))         {             string emptyText = this.EmptyText;             ef = new RectangleF(4f, (float)(this.ColumnHeadersHeight + 4), (float)(this.Width - 8), (float)((this.Height - this.ColumnHeadersHeight) - 8));             graphics.DrawString(emptyText, this.Font, Brushes.LightGray, ef);         }     }