如何从c＃中的数字范围获取元素的类型？

Question

如何从一系列数字中获取输入数据的类型，并将其与c＃中的Enum相结合？我想避免使用if / else，将其移动到某种范围，也许使用IsDefined？

    [Flags]
    public enum PaymentCodeTypes
    {
        Other = 1,
        Warranty = 2,
        Contract = 4
    }
         var PaymentCodeType = 0;
            if (paymentCode >= 80 && paymentCode <= 89)
            {
                PaymentCodeType = (int) PaymentCodeTypes.Contract;
            }
            else if (paymentCode >= 90 && paymentCode <= 99)
            {
                PaymentCodeType = (int) PaymentCodeTypes.Warranty;
            } else
            {
                PaymentCodeType = (int)PaymentCodeTypes.Other;
            }

Answer 1

您可以使用C＃8中添加的switch expression：

switch

如果要使其更短，则牺牲了可维护性：

var PaymentCodeType = (int)(paymentCode switch {
    var x when x >= 80 && x <= 89 => PaymentCodeTypes.Contract,
    var x when x >= 90 && x <= 99 => PaymentCodeTypes.Warranty,
    _ => PaymentCodeTypes.Other
});