发现pb程序halt以后没有调用,application的close事件,于是百度了一下发现
如果只使用halt,系统直接中止应用，可能会出现对象未正常释放的情况
而halt close会正常关闭主线程，这样的话application的close事件也会正常执行，所以halt应该尽量不用，推荐使用halt close
When PowerBuilder encounters Halt without the keyword CLOSE, it immediately terminates the application.
When PowerBuilder encounters Halt with the keyword CLOSE, it immediately executes the script for the Close event for the application and then terminates the application. If there is no script for the Close event at the application level, PowerBuilder immediately terminates the application