Can I do this with txt file or does it have to be XML or something.
That would be at your preference.
How would I go about this please?
What you need to do first is to read the file, System.IO namespace have tools for this. It's also in your interest to handle the file line by line, so you can use
File.ReadAllLines method.
Then for each line you want to split it up by the number key and the description value,
String.Split method can be used.
A
Dictionary(Of Tkey, Tvalue) class is typically used to hold and do lookups on unique key/value pairs, for you that should be a Dictionary(Of String, String). This lookup will be used later from a different method than the one you use to load the data, so declare the Dictionary as a private field at module level. Fill it with your key/value pairs.
Done with the loading, it's time to handle the input. One option is to use the
KeyUp event for the input TextBox, and check if user pressed the Enter key, then proceed to check the lookup table against the input text. The dictionary has a ContainsKey function that you can use to validate that the input matches a key, if it is a valid key you can retrieve the value and assign that to the description TextBox.Text property.
All help topics I linked to has code samples that should help you with each step.
