in addition to OriginalGriff, I advice you to try to understand what an error means. It is not just a message, but it is a sentence with a meaning. If it says "Trim is not a member", then it means "Trim is not a member", therefore you cannot use it as if it is a member what you do in your code:
"accountNumber(which is char).Trim"
. what you should do at this point:
1- open msdn and find out your subject in there, then see its properties, methods etc.
2- think of your aim again to see if your code matches your intention.
I think you are not using the Visual Studio IDE. I strongly advice to use it, because it has many advantages as in your case. here it is:
http://www.microsoft.com/en-us/download/details.aspx?id=40787[
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