c# - Activator.CreateInstance() - 未找到构造函数

Question

我有以下类(class):

internal class MyQueryTranslator : ExpressionVisitor, IExpressionTranslator<QueryRequest>
{

       private IReflectionManager _reflectionManager;

       internal MyQueryTranslator(IReflectionManager reflectionManager)
       {
           this._reflectionManager = reflectionManager;
       }

       //....
}

与此同时，在另一个类中，我正在尝试使用 Activator.CreateInstance() 实例化此类。方法:

internal class MyPersistenceStrategy<E> : IAsyncPersistenceStrategy<E>
     where E : class, IPersistableEntity
{

       private IReflectionManager _reflectionManager;
       private static readonly Dictionary<Type, Type> _translators;

       static MyPersistenceStrategy()
       {
             _translators = new Dictionary<Type, Type>()
             {
                  { typeof(QueryRequest), typeof(MyQueryTranslator) }
             }
       }

       private T TranslateExpression<T>(Expression expression)
       {
            if(_translators.ContainsKey(typeof(T))
                   throw new InvalidOperationException(String.Format("There is no translator for: {0}", typeof(T).Name);

            IExpressionTranslator<T> translator = 
                       (IExpressionTranslator<T>)Activator.CreateInstance(_translators[typeof(T)],
                                               BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance,
                                               null,
                                               _reflectionManager,
                                               null);

            return translator.Translate(expression);
       }

       //...

}

但是，我收到以下错误:

An unhandled exception of type System.MissingMethodException occured in mscorlib.dll
Additional information: Constructor on type XXXXX.MyQueryTranslator not found

如您所见，我正在传递适当的 BindingFlgs所以实际上可以找到构造函数。

TranslateExpression<T>方法是这样调用的:

QueryRequest request = TranslateExpression<QueryRequest>(expression);

我还应该注意到，这两个类都在同一个程序集中。

Answer 1

正如一些人所指出的，它匹配了错误的重载。参数必须是一个对象数组。

(IExpressionTranslator<T>)Activator.CreateInstance(_translators[typeof(T)],
                                           BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance,
                                           null,
                                           new object[] { _reflectionManager },
                                           null);