为什么 0/0 是 NaN 而 0/0.00 不是
Why 0/0 is NaN but 0/0.00 isn't
使用DataTable.Compute，并构建了一些案例进行测试：
dt.Compute("0/0", null); //returns NaN when converted to double
dt.Compute("0/0.00", null); //results in DivideByZero exception
我已经更改了我的代码来处理这两个问题。但是很想知道这里发生了什么？
我猜，这是因为带小数点的文字被威胁为 System.Decimal 并导致 DivideByZeroException
Integer literals [+-]?[0-9]+ are treated as System.Int32, System.Int64
or System.Double
Real literals without scientific notation, but with a decimal point,
are treated as System.Decimal. If the number exceeds the maximum or
minimum values supported by System.Decimal, then it is parsed as a
System.Double.
The exception that is thrown when there is an attempt to divide an
integral or Decimal value by zero.
对于 System.Double 它 returns Nan，因为如果操作是除法并且常量是整数，它会更改为双结果类型，根据 reference source （感谢@steve16351很高兴找到）
使用DataTable.Compute，并构建了一些案例进行测试：
dt.Compute("0/0", null); //returns NaN when converted to double
dt.Compute("0/0.00", null); //results in DivideByZero exception
我已经更改了我的代码来处理这两个问题。但是很想知道这里发生了什么？
我猜，这是因为带小数点的文字被威胁为 System.Decimal 并导致 DivideByZeroException
Integer literals [+-]?[0-9]+ are treated as
System.Int32,System.Int64orSystem.DoubleReal literals without scientific notation, but with a decimal point, are treated as
System.Decimal. If the number exceeds the maximum or minimum values supported bySystem.Decimal, then it is parsed as aSystem.Double.
The exception that is thrown when there is an attempt to divide an integral or
Decimalvalue by zero.
对于 System.Double 它 returns Nan，因为如果操作是除法并且常量是整数，它会更改为双结果类型，根据 reference source （感谢@steve16351很高兴找到）