Pass value and reference

Post:

Http://topic.csdn.net/u/20080721/02/2239b771-79b3-4a53-8fcf-a567a5fc4369.html

... The reference variable stores an address value, so all values are passed, that is, copy them.
Go to the bank to open an account and tell you the card number. When you write the card number on paper (reference variable) and tell others, others (methods) also use a piece of paper (form parameter) write down this card number, and then find the bank account through the card number in this paper.

Ask how much you have:
1. Simple (basic variables), write 100 in a piece of paper and tell you (method) that I only have 100 pieces.
2. complex (reference variable), just a piece of special paper (such paper can only be a bank card number), write the card number on this paper, and then tell you (method ), this is my bank card number (You have to record it with a special paper --> parameter). You can use this card number to check how much I have.