ASP를 배워라.Net System.Math 클래스

/*    */
Math.E;             //2.71828182845905
Math.PI;            //3.14159265358979

/*      */
Math.Abs;           //   
Math.Acos;          //   
Math.Asin;          //   
Math.Atan;          //   
Math.Atan2;         //   ,    
Math.BigMul;        //int32 * int32 = int64
Math.Ceiling;       //  >=      
Math.Cos;           //  
Math.Cosh;          //    
Math.DivRem;        //     
Math.Exp;           //  e      
Math.Floor;         //  <=      
Math.IEEERemainder; //  
Math.Log;           //    
Math.Log10;         //  10      
Math.Max;           //  
Math.Min;           //  
Math.Pow;           //  
Math.Round;         //    ,      
Math.Sign;          //   ,     -1、0、1 
Math.Sin;           //  
Math.Sinh;          //    
Math.Sqrt;          //   
Math.Tan;           //  
Math.Tanh;          //    
Math.Truncate;      //  

//Truncate()、Floor()、Ceiling()
protected void Button1_Click(object sender, EventArgs e)
{
    double n1 = Math.Truncate(Math.PI); // 3

    double n2 = Math.Floor(2.5);        // 2
    double n3 = Math.Floor(-2.5);       //-3

    double n4 = Math.Ceiling(2.5);      // 3
    double n5 = Math.Ceiling(-2.5);     //-2

    TextBox1.Text = string.Concat(n1, "
", n2, "
", n3, "
", n4, "
", n5);
}

//    (  )
protected void Button2_Click(object sender, EventArgs e)
{
    double n1 = Math.Round(0.5);  // 0
    double n2 = Math.Round(1.5);  // 2
    double n3 = Math.Round(2.5);  // 2
    double n4 = Math.Round(3.5);  // 4
    double n5 = Math.Round(-0.5); // 0
    double n6 = Math.Round(-1.5); //-2
    double n7 = Math.Round(-2.5); //-2
    double n8 = Math.Round(-3.5); //-4

    TextBox1.Text = string.Concat(n1, "
", n2, "
", n3, "
", n4, "
", n5, "
", n6, "
", n7, "
", n8);
}

//    
protected void Button3_Click(object sender, EventArgs e)
{
    double n1 = Math.Round(0.5, MidpointRounding.AwayFromZero);  // 1
    double n2 = Math.Round(1.5, MidpointRounding.AwayFromZero);  // 2 
    double n3 = Math.Round(2.5, MidpointRounding.AwayFromZero);  // 3
    double n4 = Math.Round(3.5, MidpointRounding.AwayFromZero);  // 4 
    double n5 = Math.Round(-0.5, MidpointRounding.AwayFromZero); //-1
    double n6 = Math.Round(-1.5, MidpointRounding.AwayFromZero); //-2
    double n7 = Math.Round(-2.5, MidpointRounding.AwayFromZero); //-3
    double n8 = Math.Round(-3.5, MidpointRounding.AwayFromZero); //-4

    TextBox1.Text = string.Concat(n1, "
", n2, "
", n3, "
", n4, "
", n5, "
", n6, "
", n7, "
", n8);
}

//      (0..28)   
protected void Button4_Click(object sender, EventArgs e)
{
    double n1 = Math.Round(3.126, 2);  // 3.13
    double n2 = Math.Round(3.124, 2);  // 3.12

    double n3 = Math.Round(3.125, 2);  // 3.12
    double n4 = Math.Round(3.135, 2);  // 3.14

    double n5 = Math.Round(3.125, 2, MidpointRounding.AwayFromZero);  // 3.13
    double n6 = Math.Round(3.135, 2, MidpointRounding.AwayFromZero);  // 3.14

    TextBox1.Text = string.Concat(n1, "
", n2, "
", n3, "
", n4, "
", n5, "
", n6);
}