The assertion code is executed during debugging, and if one of the conditions is found not to hold, execution statement condit assert usually stops with a message.
断言代码在调试阶段执行，如果发现某个执行代码语句条件没有得到满足，通常会给出相应信息并停止执行。
2
If you add, remove, or change a LINQ statement during a debugging session, a dialog box appears that tells you the change is not supported by Edit and Continue.