c# - 在静态类上调用重载的泛型方法

Question

我正在尝试调用 InputExtensions 上的方法静态类，以便为 HtmlHelper 类上的方法创建重载。

所以无论如何，我仍然无法调用InputExtensions 类的方法。这是我用来执行此操作的部分代码:

    Type inputExtensions = typeof(InputExtensions);
    MethodInfo methodInfo = null;
    MethodInfo genericMethod = null;
    switch (propertyViewingMode.ViewingLevel)
    {
        case 1:
            methodInfo = inputExtensions.GetMethod(methodName, new Type[] { typeof(HtmlHelper<TModel>), typeof(Expression<Func<TModel, TProperty>>), typeof(Object) });
            genericMethod = methodInfo.MakeGenericMethod(typeof(TModel), typeof(TProperty));
            result = genericMethod.Invoke(null, new object[] { helper, expression, new { @class = "readOnly", @readonly = "read-only" } }) as MvcHtmlString;
            break;
        case 2:
            methodInfo = inputExtensions.GetMethod(methodName, new Type[] { typeof(HtmlHelper<TModel>), typeof(Expression<Func<TModel, TProperty>>) });
            genericMethod = methodInfo.MakeGenericMethod(typeof(TModel), typeof(TProperty));
            result = genericMethod.Invoke(null, new object[] { helper, expression }) as MvcHtmlString;
            break;
        default:
            result = new MvcHtmlString(String.Empty);
            break;
    }

问题是 methodInfo 始终为 null，这意味着 Type.GetMethod 找不到我尝试调用的方法。

更新:请注意，当我没有为 GetMethod 方法提供 Type[] 数组时，它会抛出异常告诉我调用不明确。

更新 2:这是我尝试调用的方法:

TextBoxFor<TModel, TProperty>(HtmlHelper<TModel>, Expression<Func<TModel, TProperty>>, Object)

回答:

    Type inputExtensions = typeof(InputExtensions);
    IEnumerable<MethodInfo> methods = null;
    MethodInfo genericMethod = null;
    MethodInfo methodInfo = null;
    switch (propertyViewingMode.ViewingLevel)
    {
        case 1:
            methods = inputExtensions.GetMethods().Where(m => m.IsGenericMethod && m.Name.Equals(methodName))
                                                        .Where(x => x.GetParameters().Count() == 3);
            methodInfo = methods.FirstOrDefault(x => x.GetParameters()[2].ParameterType.FullName == "System.Object");
            if (methodInfo != null)
            {
                genericMethod = methodInfo.MakeGenericMethod(new[] { typeof(TModel), typeof(TProperty) });
                result = genericMethod.Invoke(null, new object[] { helper, expression, new { @class = "readOnly", @readonly = "read-only" } }) as MvcHtmlString;
            }
            break;
        case 2:
            methods = inputExtensions.GetMethods().Where(m => m.IsGenericMethod && m.Name.Equals(methodName))
                                                        .Where(x => x.GetParameters().Count() == 2);
            methodInfo = methods.FirstOrDefault();
            if (methodInfo != null)
            {
                genericMethod = methodInfo.MakeGenericMethod(new[] { typeof(TModel), typeof(TProperty) });
                result = genericMethod.Invoke(null, new object[] { helper, expression }) as MvcHtmlString;
            }
            break;
        default:
            result = new MvcHtmlString(String.Empty);
            break;
    }

Answer 1

不幸的是，似乎不可能... http://blogs.msdn.com/b/yirutang/archive/2005/09/14/466280.aspx

你唯一能做的就是迭代所有给定名称的方法并自己分析参数类型:(