如何在C#中使用LINQ搜索特定字符串属性的对象列表

Question

我有以下代码:

    private List<Car> Fleet = new List<Car>()
    {
       new Car("Toyota", "Corola","YI348J", 2007, 7382.33),
       new Car("Renault", "Megane","ZIEKJ", 2001, 1738.30),
       new Car("Fiat", "Punto","IUE748", 2004, 3829.33)
    };

    public void addToFleet(String make, String model, String registration, int year, Double costPrice)
    {
        Fleet.Add(new Car(make, model, registration, year, costPrice));
    }

在将新的Car对象添加到Fleet列表之前,我需要检查"registration"是否已经作为列表中任何Car对象的属性存在.此检查需要使用LINQ并在addToFleet方法中.

Answer 1

假设您的Car类有财产注册:

private List<Car> Fleet = new List<Car>()
{
   new Car("Toyota", "Corola","YI348J", 2007, 7382.33),
   new Car("Renault", "Megane","ZIEKJ", 2001, 1738.30),
   new Car("Fiat", "Punto","IUE748", 2004, 3829.33)
};

public void addToFleet(String make, String model, String registration, int year, Double costPrice)
{
    if(Fleet.Any(car => car.Registration == registration))
    {
       // already in there
    } 
    else
    {
      Fleet.Add(new Car(make, model, registration, year, costPrice));
    }
}