Question

我正在尝试创建一个工作程序，您必须输入城镇，产品和数量并输出总价格。

例如，Town1＆gt; Milk＆gt; 2应该生成2。但由于某种原因，没有产出。有人可以帮助我并告诉我错误吗？

以下是代码：

Console.Write("Enter product: ");
var product = Console.ReadLine().ToLower();
Console.Write("Enter town: ");
var town = Console.ReadLine().ToLower();
Console.Write("Enter quantity: ");
var quantity = double.Parse(Console.ReadLine());

if (town == "Town1")
{
    if (product == "Milk")
        Console.WriteLine(1.50 * quantity);
    if (product == "Water")
        Console.WriteLine(0.80 * quantity);
    if (product == "Whiskey")
        Console.WriteLine(4.20 * quantity);
    if (product == "Peanuts")
        Console.WriteLine(0.90 * quantity);
    if (product == "Chocolate")
        Console.WriteLine(2.60 * quantity);   
}
if (town == "Town2")
{
    if (product == "Milk")
        Console.WriteLine(1.40 * quantity);
    if (product == "Water")
        Console.WriteLine(0.70 * quantity);
    if (product == "Whiskey")
        Console.WriteLine(3.90 * quantity);
    if (product == "Peanuts")
        Console.WriteLine(0.70 * quantity);
    if (product == "Chocolate")
        Console.WriteLine(1.50 * quantity);
}
if (town == "Town3")
{
    if (product == "Milk")
        Console.WriteLine(1.90 * quantity);
    if (product == "Water")
         Console.WriteLine(1.50 * quantity);
    if (product == "Whiskey")
         Console.WriteLine(5.10 * quantity);
    if (product == "Peanuts")
         Console.WriteLine(1.35 * quantity);
    if (product == "Chocolate")
         Console.WriteLine(3.10 * quantity);
}
}}}

Answer 1

您正在设置town = value.ToLower()和product = value.ToLower()，这会使所有字符都小写，请更改这些行：

var town = Console.ReadLine().ToLower();
var product = Console.ReadLine().ToLower();

对此：

var town = Console.ReadLine();
var product = Console.ReadLine();

或者更改if语句条件以使用小写值作为比较

if (town == "town1")
{

等...

Answer 2

对于奖励积分，请考虑使用Dictionary<,>，这也允许您指定应执行不区分大小写的比较。

var townProductPrices = new Dictionary<string, Dictionary<string, double>>(StringComparer.CurrentCultureIgnoreCase) {
    ["Town1"] = new Dictionary<string, double>(StringComparer.CurrentCultureIgnoreCase) {
        ["Milk"] = 1.50d,
        ["Water"] = 0.80d,
        ["Whiskey"] = 4.20d,
        ["Peanuts"] = 0.90d,
        ["Chocolate"] = 2.60d,
    },
    ["Town2"] = new Dictionary<string, double>(StringComparer.CurrentCultureIgnoreCase) {
        ["Milk"] = 1.40d,
        ["Water"] = 0.70d,
        ["Whiskey"] = 3.90d,
        ["Peanuts"] = 0.70d,
        ["Chocolate"] = 1.50d,
    },
    //...
};


Console.Write("Enter product: ");
var product = Console.ReadLine().Trim();
Console.Write("Enter town: ");
var town = Console.ReadLine().Trim();
Console.Write("Enter quantity: ");
var quantity = double.Parse(Console.ReadLine().Trim());

var productPrices = townProductPrices[town];
var price = productPrices[product];
var total = price * quantity;
Console.WriteLine(total.ToString("c"));

Answer 3

你不需要这么多比赛。如果最重要的话，试试这个：

public class Program
{
    private static void Main(string[] args)
    {
        Console.Write("Enter product: ");
        var product = Console.ReadLine().ToLower();
        Console.Write("Enter town: ");
        var town = Console.ReadLine().ToLower();
        Console.Write("Enter quantity: ");
        var quantity = double.Parse(Console.ReadLine());

        var mapperData = new List<Mapper>()
                         {
                             new Mapper { TownName = "Town1", ProductInfo = "Milk", Quantity = 1.50 },
                             new Mapper { TownName = "Town1", ProductInfo = "Water", Quantity = 0.80 },
                             new Mapper { TownName = "Town1", ProductInfo = "Whiskey", Quantity = 4.20 },
                             new Mapper { TownName = "Town1", ProductInfo = "Peanuts", Quantity = 0.90 },
                             new Mapper { TownName = "Town1", ProductInfo = "Chocolate", Quantity = 2.60 },

                             new Mapper { TownName = "Town2", ProductInfo = "Milk", Quantity = 1.40 },
                             new Mapper { TownName = "Town2", ProductInfo = "Water", Quantity = 0.70 },
                             new Mapper { TownName = "Town2", ProductInfo = "Whiskey", Quantity = 3.90 },
                             new Mapper { TownName = "Town2", ProductInfo = "Peanuts", Quantity = 0.70 },
                             new Mapper { TownName = "Town2", ProductInfo = "Chocolate", Quantity = 1.50 },

                             new Mapper { TownName = "Town3", ProductInfo = "Milk", Quantity = 1.90 },
                             new Mapper { TownName = "Town3", ProductInfo = "Water", Quantity = 1.50 },
                             new Mapper { TownName = "Town3", ProductInfo = "Whiskey", Quantity = 5.10 },
                             new Mapper { TownName = "Town3", ProductInfo = "Peanuts", Quantity = 1.35 },
                             new Mapper { TownName = "Town3", ProductInfo = "Chocolate", Quantity = 3.10 },
                         };

        var matchingQuantity = mapperData.FirstOrDefault(i => i.TownName.ToString().ToLower() == town.ToLower().Trim()
                                                  && i.ProductInfo.ToString().ToLower() == product.ToLower().Trim()).Quantity;
        Console.WriteLine(matchingQuantity * quantity);
    }
}

public class Mapper
{
    public string TownName { get; set; }
    public string ProductInfo { get; set; }
    public double Quantity { get; set; }
}

此外，您甚至可以为城镇和产品创建枚举并使用它们。

为什么这段代码不能打印任何东西？

3 个答案: