【Basic computer】------ Calculator

【Basic computer】------ Calculator

Reuse VS copy

  
【Copy】: copy is pretty to all of us, just Ctrl+c and Ctrl+v;

【Reuse】: the same thing you can use it for many time .

【comparison】：for example, you want to use a car, I already  have a car, but you do not, you want use the same car as mine, copy is that you go to build a car as my 100% but reuse is different ,you just borrow the car from me and use it .

   So which is better, while we are program which is for sure that reuse is much better, because reuse is less code but copy which means you gonna to use more workspace and program more.


    

Tight coupling  VS  loose coupling

      【Tight coupling】：which is mean each function have strongly connection to themselves and all the codes at the same winform.

      【loose coupling】：there have many winforms. Each windform has their own method and just finish the things themselves. For example: three level.

     【comparison】：for example, you have a restaurant, at the first period maybe there just you alone to running it , you to service people, you go to buy the demand goods and you cook the food for customers by yourself. All these three thing you do it by you alone this what we call it Tight coupling;

  

        But what is Loose coupling? One day you restaurant is became more popular and you hire two people, person A going to service the Customers; person B is going to input some demand goods like oil, vegetables , salt and so on. So right now you are upgrade, that is mean different people have their own business which means everyone in your restaurant have clear duty and you restaurant will make more and more efficient for sure. As the same while we are designer the software and coding the code where we learn it from the real life around us.

  

【Calculator】

       First time we code all the codes on the same class which we call it tight coupling, but we want to make it more efficient ,so we changed to loose coupling. We separate  class “Program” to two classes as “Operation” and ”Program”.

                    
    

The detail codes:

 【Operation】

using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Threading.Tasks;namespace Caculator{    class Operation    {        public static double GetResult(double numberA, double numberB, string operate)        {            double result = 0d;            switch (operate)            {                case "+":                    result = numberA + numberB;                    break;                case "-":                    result = numberA - numberB;                    break;                case "*":                    result = numberA * numberB;                    break;                case "/":                    result = numberA / numberB;                    break;            }            return result;        }    }}

【program】

using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Threading.Tasks;namespace Caculator{    class Program    {        static void Main(string[] args)        {            try            {                Console.Write("Pleaser input NumberA: ");                string strNumberA = Console.ReadLine();                Console.Write("plsase input a operational sign（+、—、*、/):  ");                string strOperate = Console.ReadLine();                Console.Write("Pleaser input NumberB: ");                string strNuberB = Console.ReadLine();                string strResult = "";                strResult = Convert.ToString(Operation.GetResult(Convert.ToDouble(strNumberA), Convert.ToDouble(strNuberB), strOperate));                Console.WriteLine("The result is：" + strResult);                Console.ReadLine();            }            catch (Exception ex)            {                Console.WriteLine("You are wrong：" + ex.Message);            }        }    }}

The result show: