在C#中创建方法

Question

我将如何在C#中为以下内容创建一个方法。

如果是奇数，则应返回整数/2。如果是偶数，则应返回自身相乘的整数。如果该整数为null，则应返回12345。

任何帮助都将不胜感激谢谢

Answer 1

你是如何获得输入的？对于本例，我假设它是一个字符串，因为默认情况下int不能为null。但是，您可以使用int？创建一个可为空的int

private int MethodName(string input)
{
    //Validate the input is an int. You may want to support decimals here.
    //decimal.TryParse is the method. As dividing an odd number by 2 using an int will round.
    var validInput = Int32.TryParse(input, out var result);

    //You may want to return this if the input is 0 as well.
    if (!validInput)
        return 12345;

    //An even number will have remainder of 0 when divied by 2...
    var isEven = result % 2 == 0;

    if (isEven)
        return result * result;

    //Otherwise it must be odd
    return result / 2;
}