有的時候會把double int這類數值放在泛型方法里,就不需要寫多份了,但是這個時候也需要進行四則運算,可以寫成這個樣子
public static T Add<T>(T num1, T num2) where T : struct, IComparable { if (typeof(T) == typeof(int)) { int a = (int)Convert.ChangeType(num1, typeof(int)); int b = (int)Convert.ChangeType(num2, typeof(int)); int c = a + b; return (T)Convert.ChangeType(c, typeof(T)); } else if (typeof(T) == typeof(float)) { float a = (float)Convert.ChangeType(num1, typeof(float)); float b = (float)Convert.ChangeType(num2, typeof(float)); float c = a + b; return (T)Convert.ChangeType(c, typeof(T)); } else if (typeof(T) == typeof(double)) { double a = (double)Convert.ChangeType(num1, typeof(double)); double b = (double)Convert.ChangeType(num2, typeof(double)); double c = a + b; return (T)Convert.ChangeType(c, typeof(T)); } else if (typeof(T) == typeof(decimal)) { decimal a = (decimal)Convert.ChangeType(num1, typeof(decimal)); decimal b = (decimal)Convert.ChangeType(num2, typeof(decimal)); decimal c = a + b; return (T)Convert.ChangeType(c, typeof(T)); } return default(T); }
把需要的數值類型都得寫一遍,其他運算就照這個樣子寫