我如何检查一个数字是正的或负的c# ?


当前回答

当然没有人给出正确答案,

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

其他回答

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;
if (num < 0) {
  //negative
}
if (num > 0) {
  //positive
}
if (num == 0) {
  //neither positive or negative,
}

或者使用else if

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);
    }
}
bool positive = number > 0;
bool negative = number < 0;
int j = num * -1;

if (j - num  == j)
{
     // Num is equal to zero
}
else if (j < i)
{
      // Num is positive
}
else if (j > i) 
{
     // Num is negative
}