Question

我遇到堆栈溢出异常的问题，但我无法告诉导致异常的原因。我使用的类库包含了我需要的所有方法和对象，并从控制台应用程序运行它。

任何帮助都将不胜感激，因为这是在几个小时内完成的作业的一部分。

这是我的代码：

TrafficIncidentNotificationRadiusCalculator类

namespace TrafficIncident
{
public class TrafficIncidentNotificationRadiusCalculator
{
    public double meters;
    public double CONFIGURED_NOTIFICATION_RADIUS
    {
        get { return CONFIGURED_NOTIFICATION_RADIUS; }
        set { CONFIGURED_NOTIFICATION_RADIUS = meters; }
    }

    public List<string> GetNotificationRecipientsList(List<User> users, List<UserLocationUpdate> userLocation, TrafficIncidentReport report)
    {
        int i = 0;
        List<string> userNotificationIds = new List<string>();
        while (i < userLocation.Count)
        {
            UserLocationUpdate userLoc = userLocation.ElementAt(i);
            userNotificationIds.Add(userLoc.userNotificationId);
            Console.WriteLine(userNotificationIds.ElementAt(i));
            i++;
        } 
        return userNotificationIds;
    }
}
}

TrafficIncidentReport类

namespace TrafficIncident
{
public class TrafficIncidentReport
{
    public double[] incidentLocation;

    public double latitude
    {
        get { return latitude; }
        set { latitude = value; }
    }

    public double longitude
    {
        get { return longitude; }
        set { longitude = value; }
    }

    public void SetIncidentLocation()
    {
        incidentLocation = new double[] { latitude, longitude };
    }

    public double[] GetIncidentLocation()
    {
        return incidentLocation;
    }
}
}

用户类

namespace TrafficIncident
{
public class User
{
    public string userFName
    {
        get { return userFName; }
        set { userFName = value; }
    }

    public string userLName
    {
        get { return userLName; }
        set { userLName = value; }
    }
}
}

UserLocationUpdate类

namespace TrafficIncident
{
public class UserLocationUpdate
{
    public string userNotificationId
    {
        get { return userNotificationId; }
        set { userNotificationId = value; }
    }

    public double lastKnownLatitude
    {
        get { return lastKnownLatitude; }
        set { lastKnownLatitude = value; }
    }

    public double lastKnownLongitude
    {
        get { return lastKnownLongitude; }
        set { lastKnownLongitude = value; }
    }
}
}

然后这是运行类库的控制台应用程序：

namespace ClassLibraryTestApp
{
class Program
{

    static void Main(string[] args)
    {
        List<User> users = new List<User>();
        List<UserLocationUpdate> userLocation = new List<UserLocationUpdate>();

        User user1 = new User();
        user1.userFName = "Scott";
        user1.userFName = "Gersbank";
        users.Add(user1);

        User user2 = new User();
        user2.userFName = "John";
        user2.userFName = "Smith";
        users.Add(user2);

        User user3 = new User();
        user3.userFName = "James";
        user3.userFName = "Moore";
        users.Add(user3);

        UserLocationUpdate user1Location = new UserLocationUpdate();
        user1Location.lastKnownLatitude = 0;
        user1Location.lastKnownLongitude = 0;
        user1Location.userNotificationId = "user1";
        userLocation.Add(user1Location);

        UserLocationUpdate user2Location = new UserLocationUpdate();
        user1Location.lastKnownLatitude = 1;
        user1Location.lastKnownLongitude = 1;
        user1Location.userNotificationId = "user2";
        userLocation.Add(user2Location);

        UserLocationUpdate user3Location = new UserLocationUpdate();
        user1Location.lastKnownLatitude = 2;
        user1Location.lastKnownLongitude = 2;
        user1Location.userNotificationId = "user3";
        userLocation.Add(user3Location);

        TrafficIncidentReport trafficReport = new TrafficIncidentReport();
        trafficReport.latitude = 1;
        trafficReport.longitude = 1;
        trafficReport.SetIncidentLocation();

        TrafficIncidentNotificationRadiusCalculator TINRC = new TrafficIncidentNotificationRadiusCalculator();
        TINRC.meters = 20000;
        TINRC.GetNotificationRecipientsList(users, userLocation, trafficReport);
    }
}
}

Answer 1

这不是创建属性，定义私有字段，然后是属性本身的正确方法：在您的情况下，它将递归调用set_latitude()方法并导致堆栈溢出异常。

错：

public double latitude
{
    get { return latitude; }
    set { latitude = value; }
}

右：

private double latitude

public double Latitude
{
    get { return latitude; }
    set { latitude = value; }
}

或使用Auto-Implemented Properties：

public double Latitude { get; set; }

Answer 2

您的代码以递归赋值开头，第一次递归就在这里：

public double meters;
public double CONFIGURED_NOTIFICATION_RADIUS
{
    get { return CONFIGURED_NOTIFICATION_RADIUS; }
    set { CONFIGURED_NOTIFICATION_RADIUS = meters; }
}

出了什么问题：

每当你为某个属性设置一些值时，它的setter就会触发，每当你访问一个属性的值时，setter就会触发。在上述情况下，您要分配财产它的值将会反复触发setter和你得到了例外

查看您的所有getter和setter都是错误的，您应该使用备份变量，或者将它们用作{get;set}。在userNotificationId的情况下，您应该像下面这样定义属性：

private _UserNotificationId
public string UserNotificationId
{
    get { return _UserNotificationId; }
    set { _UserNotificationId= value; }
}

或者只是

public string UserNotificationId { get; set; }

堆栈溢出异常，没有递归

2 个答案: