20190325-C#學習日誌

// For Loop

for(int i = 0; i < 5; i++)
{
     Console.WriteLine(i);
}

int [] myNumbers = {10, 20, 30, 40, 50};

for(int i = 0; i < myNumbers.Length; i++)
{
     Console.WriteLine(myNumbers[i]);
}

/*--------------------------------------------------------------------------------------------------*/

// Foreach Loop

char [] message = {'H', 'e', 'l', 'l', 'o'};

foreach(char i in message)
{
     Console.WriteLine(i);
}

/*--------------------------------------------------------------------------------------------------*/

// While

int counter = 5;

while(counter > 0)
{
     Console.WriteLine("Counter = {0}", counter);
     counter--;
}

/*--------------------------------------------------------------------------------------------------*/

// Do while

int counter = 100;

do
{
     Console.WriteLine("Conter = {0}", counter);
     counter++;
}
while (counter < 0);

/*--------------------------------------------------------------------------------------------------*/

// break

for(int i = 0; i < 5; i++)
{
     Console.WriteLine("i = {0}", i);
     if(i == 2)
     break;
}

/*--------------------------------------------------------------------------------------------------*/

// continue

for(int i = 0; i < 5; i++)
{
     Console.WriteLine("i = {0}", i);
     if(i == 2)
           continue;
     Console.WriteLine("I will not be printed if i = 2.\n");
}

/*--------------------------------------------------------------------------------------------------*/

//異常處理 Exception Handing

int numerator, denominator;

Console.Write("Please enter numerator: ");
numerator = Convert.ToInt32(Console.ReadLine());

Console.Write("Please enter denominator: ");
denominator = Convert.ToInt32(Console.ReadLine());

try //嘗試
{
     Console.WriteLine("The result is {0}", numerator / denominator);
}
catch(Exception e) //例外的處理方法
{
     Console.WriteLine(e.Message);
}
finally //不論是否發生例外都會執行
{
     Console.WriteLine("--- End of Error Handling Example ---");
}

/*--------------------------------------------------------------------------------------------------*/

//特定異常處理


catch(DivideByZeroException e) //除數等於零
{
     Console.WriteLine(e.Message);
}

int numerator, denominator;

try
{
     Console.Write("Please enter numerator: ");
     numerator = Convert.ToInt32(Console.ReadLine());

     Console.Write("Please enter denominator: ");
     denominator = Convert.ToInt32(Console.ReadLine());
}
catch(FormatException e)
{
     Console.WriteLine("Error: You did not enter an integer");
}
catch(DivideByZeroException)
{
     Console.WriteLine(e.Message);
}

/*--------------------------------------------------------------------------------------------------*/

 //聲明屬性

private  string nameOfStaff;
private const int hourlyRate = 30;
private int hWorked;

public int HoursWorked
{
     get
     {
          return hWorked;
     }
     set
     {
          if(value > 0)
          {
               hWorked = value;
          }
          else
          {
               hWorked = 0;
          }
     }
}

//如果沒有任何邏輯，可以使用以下簡短資料
public int HoursWorked {get; set;}

/*--------------------------------------------------------------------------------------------------*/

//聲明方法

public void PrintMessage()
{
     Console.WriteLine("Calculating Pay...");
}

public int CalculatePay()
{
     PrintMessage();

     int staffPay;
     staffPay = hWorked * hourlyRate;

     if(hWorked > 0)
          return staffPay;
     else
          return 0;
}

/*--------------------------------------------------------------------------------------------------*/

// C#允許不同方法使用同名(參數需不同)

public int CalculatePay()
{
     PrintMessage();

     int staffPay;
     staffPay = hWorked * hourlyRate;

     if(hWorked > 0)
          return staffPay;
     else
          return 0;
}

publice int CalculatePay(int bonus, int allowance)
{
     PrintMessage();

     int staffPay;
     staffPay = hWorked * hourlyRate + bonus + allowance;

     if(hWorked > 0)
          return staffPay;
     else
          return 0;
}

/*--------------------------------------------------------------------------------------------------*/

// ToString()的方法

//重寫方法 override

public override string ToString()
{
     return "Name of Staff = " + nameOfStaff + " Hour Rate = " + hourlyRate +
     " Hours Worked = " + hWorked;
}