點擊XCode中左上角三角符號练对，此符號的作用是：
Build and then run the current scheme.
Run，Test纲爸，Profile, Analyze的區(qū)別是：
?Run will build and run the target on the selected device or simulator.
?Test will build your target and run its unit tests (YourTargetNameTests.m)
?Profile will build and run your target on the selected device or simulator with an Instruments tool of your choosing (Leaks, Allocations, etc.)
?Analyze will build your target using the static analyzer and let you know of certain types of bugs in your code.
