关于VS编译器内的一个小BUG,循环内实例化对象引起的。

这个不是bug，因为随机数的种子是一个整数，默认值来自于系统时钟。你在while中连续创建random对象，由于间隔时间太短，导致默认种子是一样的，因此next输出也是一样的。

官方解释：
In .NET Framework, the default seed value is derived from the system clock, which has finite resolution. As a result, different Random objects that are created in close succession by a call to the parameterless constructor have identical default seed values and, therefore, produce identical sets of random numbers. You can avoid this problem by using a single Random object to generate all random numbers。