(The Three20 series of articles have not been updated for a long time. We can't stop our program ape on the way of learning. Today, we should first learn about ASI and JSON's knowledge of begging for data from the server. Once, MOMO told everyone to go to GitHub to see the tools written by foreigners. This website is really fun. The AIS and JSON mentioned today are open source libraries written by foreigners on GitHub. At the beginning of this article, I was wordy. My suggestion when developing with Three20 is Three20 FMDB ASI JSON. FMDB is a kind of database for database operation. This data includes the following attachments:)