C＃编译器是否转换并存储静态变量？

Question

My program uses the code:

Convert.ToDouble(Int32.MaxValue)

Fairly regularly. I was just curious about how this is handled by the compiler. Is it stored as a static double or is it executed in run time?

Answer 1

The constant Int32.MaxValue is stored at compile time, and in fact your code would be converted to Convert.ToDouble(0x7FFFFFFF) at compile time. The equivalent IL is:

ldc.i4      FF FF FF 7F 
call        System.Convert.ToDouble

This value is also saved so it can be retrieved at run-time through reflection.

However, Convert.ToDouble is a function that is only evaluated at run-time.

As minitech suggests, (double)Int32.MaxValue is evaluated at compile-time. The equivalent IL is:

ldc.r8      00 00 C0 FF FF FF DF 41