当任何数学运算在.net 4中产生’NaN’时，如何强制C＃编译器抛出exception？

我有一个很复杂的源代码，我需要找到变量值设置为nan的确切位置。 所以我需要编译器在那时抛出一个exception。 之前已经问过这个问题。 我发现以下答案是一个很好的答案。 此代码在.net 3.5中运行良好。但是当我使用.net 4时，此解决方案无法正常工作。 即使我在调试器中启用“抛出exception时中断”，也无法在代码中找到exception。 任何的想法？

using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; using System.Runtime.InteropServices; namespace ConsoleApplication2 { class Program { [System.Runtime.InteropServices.DllImport("msvcrt.dll")] public static extern uint _control87(uint a, uint b); [System.Runtime.InteropServices.DllImport("msvcrt.dll")] public static extern uint _clearfp(); static void Main(string[] args) { float zero = 0.0f - args.Length; // Want 0.0f. Fool compiler... System.Console.WriteLine("zero = " + zero.ToString()); // A NaN which does not throw exception float firstNaN = zero / 0.0f; System.Console.WriteLine("firstNaN= " + firstNaN.ToString()); // Now turn on floating-point exceptions uint empty = 0; uint cw = _control87(empty, empty); // Debugger halts on this one and complains about false signature, but continue works. System.Console.WriteLine(cw.ToString()); uint MCW_EM = 0x0008001f; // From float.h uint _EM_INVALID = 0x00000010; // From float.h (invalid corresponds to NaN // See https://www.fortran-2000.com/ArnaudRecipes/CompilerTricks.html#x86_FP cw &= ~(_EM_INVALID); _clearfp(); // Clear floating point error word. _control87(cw, MCW_EM); // Debugger halts on this one and complains about false signature, but continue works. System.Console.WriteLine(cw.ToString()); // A NaN which does throw exception float secondNaN = 0; try { // Put as much code here as you like. // Enable "break when an exception is thrown" in the debugger // for system exceptions to get to the line where it is thrown // before catching it below. secondNaN = zero / 0.0f; } catch (System.Exception ex) { _clearfp(); // Clear floating point error word. } System.Console.WriteLine("secondNaN= " + secondNaN.ToString()); } } } 

 [System.Runtime.InteropServices.DllImport("msvcrt.dll", CallingConvention = System.Runtime.InteropServices.CallingConvention.Cdecl)] public static extern uint _controlfp(uint a, uint b); [System.Runtime.InteropServices.DllImport("msvcrt.dll", CallingConvention = System.Runtime.InteropServices.CallingConvention.Cdecl)] public static extern uint _clearfp(); 

 struct DoubleNoNan { public readonly double Value; public DoubleNoNan(double value) { if (Double.IsNaN(value)) { throw new Exception("NaN"); } this.Value = value; } public static implicit operator double(DoubleNoNan value) { return value.Value; } public static implicit operator DoubleNoNan(double value) { return new DoubleNoNan(value); } public override bool Equals(object obj) { return this.Value.Equals(obj); } public override int GetHashCode() { return this.Value.GetHashCode(); } public override string ToString() { return this.Value.ToString(); } } 

 DoubleNoNan dn = 0.0; dn = / 0.0;