Question

这可能相当简单，但我遇到的问题是返回“环”值，这是我的代码。

double circRad = 0;
double circum = 0;

if(userOption == 2){

        circRad = myRad();
        System.out.println("The Radius of the circle is " + circRad + " and it perimeter is "+ circum);

public static double myRad(){

    int i= 1;
    double circRad = 0;
    Scanner myInput=new Scanner(System.in);

    switch(i)
    {
        case 1:
        System.out.print("Please enter a positive Radius for the circle ");
        circRad = myInput.nextDouble();
        while(circRad <0){
            System.out.print("Please enter a POSITIVE Radius for the circle ");
            circRad = myInput.nextDouble();
            }
                ++i;
    }
    return circRad;
}

public static double myRad(double circRad){

    double circum = 0;

    circum = 2* Math.PI * circRad;

    return circum;
}

Answer 1

也许你错过了以下内容：

if(userOption == 2){
    circRad = myRad();
    circum  = myRad(circRad); // <-- missing setting local circum value
    System.out.println("The Radius of the circle is " + circRad + " and it perimeter is "+ circum);
}

Answer 2

我只能用它呈现的方式来猜测代码是circRad和circum是全局变量，因此当你调用第一个myRad()时，只有circRad会发生变化。但是，circum仍为0。如果你可以发送整个代码，它会让一切变得更容易。

使用方法计算圆周长

2 个答案: