It's been a while since I've used Delphi...but if I remember correctly, you'll need to do the following:
- Populate TComboBox.Items[] with a list of filenames stored as Strings. If I'm not mistaken, this is a dynamic Array of String. There's a method already provided that will let you add String variables: TComboBox.Items.Add(). Alternatively, if this doesn't have to be changed during program operation, just use the properties window to fill in Items yourself using the […] button.
- When the user clicks something to confirm their selection, or hits enter, read the selected item from the TComboBox. Store that data (i.e. a filename) in a String.
- Read the file's contents. Note that even if it's a .txt file, there are multiple ways of reading it in.
- If you assign a variable of type TextFile (equivalent to type Text), it's sequential-access, and you'll need to parse it somehow. This depends on the input specification.
- If you use type File (or File of [some type]), you'll probably get a mess. But you're stuck with it if you need random-access capability.
Either way, you'll need to use AssignFile() with the file variable (of type TextFile, File or File of [some type]) and the filename (of type String). Also, you'll need to use Reset() and CloseFile(). - If you want to put data into a TMemo, you might consider reading a TextFile line-by-line with ReadLn(), and then outputting the result to TMemo.Lines[] (dynamic Array of String).
Check the help file or
http://www.delphibasics.co.uk for more information on the specific functions and types.
Incidentally, as was noted by FourPenguins, this forum is typically devoted to the FIRST Robotics Competition, and discussion of related topics.