过分了!

public static class AwesomeExtensions
{
    public static bool IsPositive(this int number)
    {
        return number > 0;
    }

    public static bool IsNegative(this int number)
    {
        return number < 0;
    }

    public static bool IsZero(this int number)
    {
        return number == 0;
    }

    public static bool IsAwesome(this int number)
    {
        return IsNegative(number) && IsPositive(number) && IsZero(number);
    }
}

过分了!

public static class AwesomeExtensions
{
    public static bool IsPositive(this int number)
    {
        return number > 0;
    }

    public static bool IsNegative(this int number)
    {
        return number < 0;
    }

    public static bool IsZero(this int number)
    {
        return number == 0;
    }

    public static bool IsAwesome(this int number)
    {
        return IsNegative(number) && IsPositive(number) && IsZero(number);
    }
}

这是行业标准:

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

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

对于32位有符号整数，例如System。Int32，也就是c#中的int:

bool isNegative = (num & (1 << 31)) != 0;

num < 0 // number is negative