How do I check if a number is positive or negative in C#?

Question

How do I check if a number is positive or negative in C#?

Answer 1

First parameter is stored in EAX register and result also.

function IsNegative(ANum: Integer): LongBool; assembler;
asm
   and eax, $80000000
end;

Answer 2

You just have to compare if the value & its absolute value are equal:

if (value == Math.abs(value))
    return "Positif"
else return "Negatif"

Answer 3

bool positive = number > 0;
bool negative = number < 0;

Answer 4

This is the industry standard:

int is_negative(float num)
{
  char *p = (char*) malloc(20);
  sprintf(p, "%f", num);
  return p[0] == '-';
}

Answer 5

Of course no-one's actually given the correct answer,

num != 0   // num is positive *or* negative!

Answer 6

The Math.Sign method is one way to go. It will return -1 for negative numbers, 1 for positive numbers, and 0 for values equal to zero (i.e. zero has no sign). Double and single precision variables will cause an exception (ArithmeticException) to be thrown if they equal NaN.