Question

I have this on a button:

private void Button_Click(object sender, RoutedEventArgs e)
{
    string s = "x12y04";

    //make new instance for MyMath class
    MyMath dRet01 = new MyMath();

    //use the doubleArrayXY (in MyMath class) to get doubble array back
    double[] retD = dRet01.doubleArrayXY(s);

    //use the calcResultFromDoubleArray (in MyMath class) to get result
    MyMath dRet02 = new MyMath();
    double result = dRet02.calcResultFromDoubleArray(retD[0], retD[1]);

    //DEBUG!
    /*
    string TEST1 = Convert.ToString(returnedDouble[0]);
    MessageBox.Show(TEST1);
    string TEST2 = Convert.ToString(returnedDouble[1]);
    MessageBox.Show(TEST2);
    string TEST3 = Convert.ToString(result);
    MessageBox.Show(TEST3);
   */


}

where the class “MyMath” is:

public double[] doubleArrayXY(string inputValue)
{
    //in case there are upper case letters, set all to lower
    string inpLow = inputValue.ToLower();

    //split the string on the Y (so this tech should also work for x89232y329)
    //so this will create res[0] that is x89232 and an res[1] that is 329
    string[] res = inpLow.Split(new string[] { "y" }, StringSplitOptions.None);

    //in the first string that looks like x89232, remove the x
    string resx = res[0].Replace("x", null);

    //now get the x value to a double
    double x = double.Parse(resx);
    //now get the y valye to a double
    double y = double.Parse(res[1]);

    //return in a double array the x and then the y (x=double[0] and y=double[1])
    return new double[] {x,y};
}

public double calcResultFromDoubleArray(double one, double two)
{
    return (one * two);
}

Now I know the part in the class that is “calcResultFromDoubleArray” is kind of useless at this point, but I want to make that do some extra stuff later on.

what I wonder about the most is in the main code where I make this new dRet10, and later on make dRet02.

I was thinking at first I could do something like this:

double result = dRet01.calcResultFromDoubleArray(retD[0], retD[1]);

So in that case I would not need to create a new instance of MyMath, but this does not work.

So I need to call a new instance for the class (like I did), or can I do this in a more elegant way?
I’m still kind of new to C#, so I’m trying to learn how to program in a nice and elegant way, besides just making it work.

Answer 1

Since your methods don’t really use any other state information besides the parameters passed they probably should be static so you would not have to create any instances of your class at all:

double[] retD = MyMath.DoubleArrayXY(s);
double result = MyMath.CalcResultFromDoubleArray(retD[0], retD[1]);

If all of your methods in MyMath are static, declare the class itself static – just like the System.Math class, so you cannot create instances at all.