You are going to have to add an event handler for OnChange so that you check the input on edit.

There are several issues with what is going on here.. After looking the code its important to note the file.end is not doing what you want it to do. If you look at the definition of the data member it is returning an enumeration to the end of the file. It is not whether or not you are currently at the EOF. Also the methods you are using STOP on a EOF character because you are reading in the default text mode. You should be opening the file in binary read mode " CFile::typeBinary". Because of the special characters I would suggest that you tseek the end of file get the length of the file and then do a for loop to retrieve the data out of the file.

A Simple search of code project yields a number of jewels. ^[] there are a lot of things to consider when you begin trying to use windows office automation not the least of which C++ isn't the "best choice". VB ultimately is a much better choice for this type of task(native language for excel). Also for deployment will the target users all have office? will they have the "right" version of office? Do you really need to write a full blown app or will VB scripting do the job? Excel objects are setup just like the in the program books, pages, range and cell.