Question

我有一点问题，在我的源代码中我不明白为什么我的ToUpload方法在Console窗口中给我一个额外的console.writeLine。（写出啤酒对象）

当我调用ToUpload方法，并且啤酒在啤酒词典中时，它会给我一个额外的Console.WriteLine，在那里写出控制台上的啤酒对象。我不知道为什么。

这是我的输出：

Borsodosör1604.6 1000
Pilsner Urquell 250 4.4 800
SoproniÁszok150,4.5900
Dreher Classic 200,5.2 600
125
Borsodosör1604.6 475
Pilsner Urquell 250 4.4 800
SoproniÁszok150,4.51350
Dreher Classic 200,5.2 600
Bratisosör，230,4.5 300
SoproniÁszok150,4.5450 //这是额外的
Borsodosör1604.6 100 //这是

我希望如此：

Borsodosör1604.6 1000
Pilsner Urquell 250 4.4 800
SoproniÁszok150,4.5900
Dreher Classic 200,5.2 600
125
Borsodosör1604.6 475
Pilsner Urquell 250 4.4 800
SoproniÁszok150,4.51350
Dreher Classic 200,5.2 600

Bratisosör，230,4.5 300

public void ToUpload(Beer beer, int dl)
{
    int d = 0;
    Beer s = null;
    // search for beer in beers dictionary
    foreach (var item in beers)
    {
        if (item.Key.Equals(beer))
        {
            d = item.Value;
            s = item.Key;
        }
    }
    // if this beer in the beers, update the value
    if (s != null)
    {
        beers[s] = d + dl;
    }
    // if a new beer, just add to beers
    beers.Add(beer, dl); // IDictionary beers = new Dictionary
}

public Pub()
{
    ToUpload(new Beer("Borsodi beer", 160, 4.6), 1000);
    ToUpload(new Beer("Pilsner Urquell", 250, 4.4), 800);
    ToUpload(new Beer("Soproni Ászok", 150, 4.5), 900);
    ToUpload(new Beer("Dreher Classic", 200, 5.2), 600);
}

static void Main(String[] args)
{
    Beer b = new Beer("Borsodi beer", 160, 4.6);
    Beer c = new Beer("Bratista beer", 230, 4.5);
    Beer d = new Beer("Soproni Ászok", 150, 4.5);
    Pub pub = new Pub();
    foreach (var item in pub.beers)
    {
        Console.WriteLine("{0} {1}", item.Key, item.Value);

    }


    Console.WriteLine(pub.Elad("Borsodi beer", 125));


    //pub.ToUpload(b, 2000);
    pub.ToUpload(c, 300); // Don't Write out this beer object
    pub.ToUpload(d, 450); // Write out this beer object the console
    pub.ToUpload(b, 100); // Write out this beer object the console



    foreach (var item in pub.beers)
    {
        Console.WriteLine("{0} {1}", item.Key, item.Value);

    }

    Console.ReadLine();

以下是Beer类：

public class Beer
{
    string name;
    int price; 
double alcohol;

public string Name { get { return name; } }

public int Price{ get; set; }

public double AlkoholTartalom { get { return alcohol; } }

public Beer(string name, int price, double alcohol)
{
    // ide írja a kódot
    this.name = name;
    this.price = price;
    this.alcohol = alcohol;
}

public override bool Equals(object obj)
{
    if (obj is Beer)
    {
        Beer other = (Beer)obj;
        return this.name == other.name;
    }
    return false;
}

public override string ToString()
{
    return this.Name + " " + this.Price+ " " + this.AlkoholTartalom;
}
}

Answer 1

您在ToUpload方法中缺少“Else”。

// if this beer in the beers, update the value
if (s != null)
{
    beers[s] = d + dl;
}
else  // Add this 
    beers.Add(beer, dl); // IDictionary beers = new Dictionary

从我看到的，这应该解决它。你正在将啤酒添加到字典中，即使你应该更新它。

Answer 2

根据啤酒的类型，您可以这样做：

public void ToUpload(Beer beer, int dl)
{
    int d = 0;
    if(beers[beer] != null)
        d = beers[beer];

    beers[beer] = d + dl;
}

我知道HashTables会根据是否以这种方式访问密钥而自动更新或添加到字典中。

C＃方法给我一个额外的Console.WriteLine

2 个答案: