Sqlite数据库无法删除对象，失败消息为“0”；无法存储类型：<；类型>&引用；

我正在尝试删除存储在Sqlite数据库中的类型的记录。它失败，并显示以下消息：

"Cannot store type: MyNamespace.PanelLog"

我有以下删除记录的方法：

    public static int DeletePanelLog(int id)
    {
        return me.db.DeleteItem<PanelLog>(id);
    }

以下是来自SQLite的调用堆栈：

    public int Delete<T>(object primaryKey)
    {
        var map = GetMapping(typeof(T));
        var pk = map.PK;
        if (pk == null)
        {
            throw new NotSupportedException("Cannot delete " + map.TableName + ": it has no PK");
        }
        var q = string.Format("delete from \"{0}\" where \"{1}\" = ?", map.TableName, pk.Name);
        return Execute(q, primaryKey); // in this case, primaryKey is a PanelLog object
    }

    public int Execute(string query, params object[] args)
    {
        var cmd = CreateCommand(query, args);

        if (TimeExecution)
        {
            if (_sw == null)
            {
                _sw = new Stopwatch();
            }
            _sw.Reset();
            _sw.Start();
        }

        var r = cmd.ExecuteNonQuery();

        if (TimeExecution)
        {
            _sw.Stop();
            _elapsedMilliseconds += _sw.ElapsedMilliseconds;
            Debug.WriteLine(string.Format("Finished in {0} ms ({1:0.0} s total)", _sw.ElapsedMilliseconds, _elapsedMilliseconds / 1000.0));
        }

        return r;
    }

    public int ExecuteNonQuery()
    {
        if (_conn.Trace)
        {
            Debug.WriteLine("Executing: " + this);
        }

        var r = SQLite3.Result.OK;
        var stmt = Prepare();
        r = SQLite3.Step(stmt);
        Finalize(stmt);
        if (r == SQLite3.Result.Done)
        {
            int rowsAffected = SQLite3.Changes(_conn.Handle);
            return rowsAffected;
        }
        else if (r == SQLite3.Result.Error)
        {
            string msg = SQLite3.GetErrmsg(_conn.Handle);
            throw SQLiteException.New(r, msg);
        }
        else
        {
            throw SQLiteException.New(r, r.ToString());
        }
    }

    Sqlite3Statement Prepare()
    {
        var stmt = SQLite3.Prepare2(_conn.Handle, CommandText);
        BindAll(stmt);
        return stmt;
    }

    void BindAll(Sqlite3Statement stmt)
    {
        int nextIdx = 1;
        foreach (var b in _bindings)
        {
            if (b.Name != null)
            {
                b.Index = SQLite3.BindParameterIndex(stmt, b.Name);
            }
            else
            {
                b.Index = nextIdx++;
            }

            BindParameter(stmt, b.Index, b.Value, _conn.StoreDateTimeAsTicks);
        }
    }

它似乎试图绑定对象类型，而不是对象的值。这是正确的吗？我能做些什么来解决这个问题吗

编辑：

经过一些进一步的测试，似乎以下工作：

    public int Delete(object objectToDelete)
    {
        var map = GetMapping(objectToDelete.GetType());
        var pk = map.PK;
        if (pk == null)
        {
            throw new NotSupportedException("Cannot delete " + map.TableName + ": it has no PK");
        }
        var q = string.Format("delete from \"{0}\" where \"{1}\" = ?", map.TableName, pk.Name);
        return Execute(q, pk.GetValue(objectToDelete));
    }

而不是使用：

   public int DeleteItem<T>(int id) where T : IBusinessEntity, new()
    {
        lock (locker) {
    #if NETFX_CORE
            return Delete(new T() { ID = id });
    #else
            return Delete<T> (new T () { ID = id });
    #endif
        }
    }

---

我也遇到了这个问题。实际上，它来自DeleteItem定义中的一行：

return Delete<T> (new T () { ID = id });

返回Delete（newt（）{ID=ID}）；

应该是：

return Delete<T> (id);

返回删除（id）；

便捷的解决方案！谢谢。我从中得到了这个ORM-也许你可以在你的问题中添加一两个标签来帮助人们发现它更容易<代码>Xamarin也许？它不是来自SQLite代码。它来自一些（沙马林？）样品。就像这个：这应该是正确的答案，谢谢。这是我在Tasky Pro示例中看到的第二个问题，我将不得不对前面提供的示例稍加说明

   public int DeleteItem<T>(int id) where T : IBusinessEntity, new()
    {
        lock (locker) {
    #if NETFX_CORE
            return Delete(new T() { ID = id });
    #else
            return Delete<T> (new T () { ID = id });
    #endif
        }
    }

   public int Delete(object objectToDelete)
    {
        var map = GetMapping(objectToDelete.GetType());
        var pk = map.PK;
        if (pk == null)
        {
            throw new NotSupportedException("Cannot delete " + map.TableName + ": it has no PK");
        }
        var q = string.Format("delete from \"{0}\" where \"{1}\" = ?", map.TableName, pk.Name);
        return Execute(q, pk.GetValue(objectToDelete));
    }

return Delete<T> (new T () { ID = id });

return Delete<T> (id);