Excuse me my explanation was a little short in my first mail.

I have a simple Table (Articles.dbf) with three columns, art_name, buy_price, sale_price. I create a simple Form with four TextBoxs, one for the article name, one for the buy price, one for the sale price and a toolbar with commandbuttons, forward, backward etc.. The fourth TexBox is like a virtual TextBox where I can display the result from two Columns from this Table or two different Tables. For connecting a TexBox with a column in the Table I use ControleSource (Thisform.Textbox1.ControleSource = “Articles.art_name”). So far no problem. But if I want display two columns in the fourth TexBox like (Thisform.TexBox4.ControleSource = “Articles.buy_price – Articles.sale_price” a error occur.

In a Grid I can create a fourth coulmn with (Thisform.grid1.Column4.ControlSource = “Articles.buy_price – Articles.sale_price”) and the result is a virtual column with the difference between the buy_price and sale_price. This aloso works with Strings or Functions like (Thisform.grid1.Column4.ControlSource = “UPPER(Articles.art_name )”). With a Grid that works very well but I can’t do the same with a simple TextBox in a Form. Somebody now way and if there is a solution to make this?

I now, my English is not perfect but I hope someone understand my problem.

Thanks