Question

这样可行，但Resharper在评论行上说“访问处置关闭”

using (var db = new SQLiteConnection(SQLitePath))
            {
                db.CreateTable<Locations>();

                db.RunInTransaction(() =>
                {
                    db.Insert(new Locations // Resharper: "Access to disposed closure" ???
                    {
                        PersonId = personId,
                        Latitude = latitude,
                        Longitude = longitude,
                        SentTimeUTC = sentTimeUTC,
                        ReceivedTimeLocal = receivedTimeLocal,
                        CivicAddress = civicAddress
                    });
                });
            }

这种替代方法也有效，但与Resharper的指纹相同：

    var db = new SQLiteConnection(SQLitePath);
    {
        db.CreateTable<Locations>();

        db.RunInTransaction(() =>
        {
        　　　　db.Insert(new Locations // this works, although Resharper warns: "Access to disposed closure" ???
               {
               　　　　PersonId = personId,
                      Latitude = latitude,
                      Longitude = longitude,
                      SentTimeUTC = sentTimeUTC,
                      ReceivedTimeLocal = ReceivedTimeLocal,
                      CivicAddress = civicAddress
              　});
        });
    }
    db.Dispose();

它们都有效，所以我猜它没关系太多，但是另一种方式更好吗？有没有办法安抚Resharper并仍然完成工作？

更新

Donal所说的似乎是明智的，但我仍然在xaction中的Insert语句中使用这个重构代码获得Resharper“潜在代码质量问题”警告：

public void InsertLocationRecord(string personId, double latitude, double longitude,
    DateTime sentTimeUTC, DateTime receivedTimeLocal, string civicAddress) 
{
    Locations locs = new Locations { PersonId = personId,
                                     Latitude = latitude,
                                     Longitude = longitude,
                                     SentTimeUTC = sentTimeUTC,
                                     ReceivedTimeLocal = receivedTimeLocal,
                                     CivicAddress = civicAddress
                                   };

    using (var db = new SQLiteConnection(SQLitePath))
    {
        db.CreateTable<Locations>();

        db.RunInTransaction(() =>
                                {
                                    db.Insert(locs); // Still get, "Access to disposed closure" on this line.
                                });
    }
}

也许我以错误的方式重构问题？我想这与以前的方式并没有太大的不同;我如何确保locs实例被处理？或者这不是问题吗？

Answer 1

问题是你正在中间创建一个Locations的自定义子类，它可以获取当前上下文中不需要的各种东西，而ReSharper正在接受那（并且无法证明它不会以某种方式逃脱）。最简单的修复方法实际上是将构造函数（或构造函数，如果需要）添加到Locations，以允许您使用所有正确的值实例化它而不进行闭包捕获。

Answer 2

第1步： 假设您的Location类中的代码是这样的。

class Locations { 
    int PersonId;
    int Latitude;
    int Longitude;
    int SentTimeUTC;
    int ReceivedTimeLocal;
    int CivicAddress;

    // Functions;

    // {
    // Disposable resource
    // }
    public Locations (latitude,longitude,sentTimeUTC,receivedTimeLocal,civicAddress)
    {
        PersonId = personId;
        Latitude = latitude;
        Longitude = longitude;
        SentTimeUTC = sentTimeUTC;
        ReceivedTimeLocal = receivedTimeLocal;
        CivicAddress = civicAddress;
    };
};

将您的班级更改为IDisposable类。

class Locations : IDisposable { 
    int PersonId;
    int Latitude;
    int Longitude;
    int SentTimeUTC;
    int ReceivedTimeLocal;
    int CivicAddress;

    // Functions;

    // {
    // Disposable resource
    // }
    public Locations (latitude,longitude,sentTimeUTC,receivedTimeLocal,civicAddress)
    {
        PersonId = personId;
        Latitude = latitude;
        Longitude = longitude;
        SentTimeUTC = sentTimeUTC;
        ReceivedTimeLocal = receivedTimeLocal;
        CivicAddress = civicAddress;
    }

    public void Dispose() {
        Dispose(true);
        GC.SuppressFinalize(this);
    }

    protected virtual void Dispose(bool disposing) {
        if (disposing) {
            // Free your disposable resources here
            base.Dispose(disposing);
        }
    }
};

第2步： 然后将您的呼叫更改为原始代码

Locations locs = new Locations { PersonId = personId,
         Latitude = latitude,
         Longitude = longitude,
         SentTimeUTC = sentTimeUTC,
         ReceivedTimeLocal = receivedTimeLocal,
         CivicAddress = civicAddress
       };
using (var db = new SQLiteConnection(SQLitePath))
{
db.CreateTable<Locations>();

db.RunInTransaction(() =>
    {
        db.Insert(locs); // Still get, "Access to disposed closure" on this line.
    });
}

到

using (Locations locs = new Locations { PersonId = personId,
         Latitude = latitude,
         Longitude = longitude,
         SentTimeUTC = sentTimeUTC,
         ReceivedTimeLocal = receivedTimeLocal,
         CivicAddress = civicAddress
    }) {
    using (var db = new SQLiteConnection(SQLitePath))
    {
    db.CreateTable<Locations>();

    db.RunInTransaction(() =>
        {
            db.Insert(locs); // Still get, "Access to disposed closure" on this line.
        });
    }
}

SQLiteConnection是否在Transaction内部处理？

更新

2 个答案: