这就是我开始处理这个问题的方式。根据 FormKey 属性（可以由索引和/或标签确定，具体取决于），自定义模型绑定器将非常容易构建。
public class CustomFormModel
{
public string FormId { get; set; }
public string Label { get; set; }
public CustomFieldModel[] Fields { get; set; }
}
public class CustomFieldModel
{
public DataType DateType { get; set; } // System.ComponentModel.DataAnnotations
public string FormKey { get; set; }
public string Label { get; set; }
public object Value { get; set; }
}
public class CustomFieldModel<T> : CustomFieldModel
{
public new T Value { get; set; }
}
另外，我注意到下面的其中一个 cmets 有一个过滤模型活页夹系统。来自 Automapper 的 Jimmy Bogard 在 http://www.lostechies.com/blogs/jimmy_bogard/archive/2009/03/17/a-better-model-binder.aspx 上发表了一篇关于此方法的非常有用的帖子，后来在 http://www.lostechies.com/blogs/jimmy_bogard/archive/2009/11/19/a-better-model-binder-addendum.aspx 中进行了修改。它对我构建自定义模型绑定器非常有帮助。
更新
我意识到我误解了这个问题，他专门询问如何处理“具有代表不同数据类型的可变数量的输入字段”的表单的发布。我认为最好的方法是使用与上面类似的结构，但利用Composite Pattern。基本上，您将需要创建一个类似IFormComponent 的接口，并为要表示的每个数据类型实现它。我编写并评论了一个示例界面，以帮助解释如何实现这一点：
public interface IFormComponent
{
// the id on the html form field. In the case of a composite Id, that doesn't have a corresponding
// field you should still use something consistent, since it will be helpful for model binding
// (For example, a CompositeDateField appearing as the third field in the form should have an id
// something like "frmId_3_date" and its child fields would be "frmId_3_date_day", "frmId_3_date_month",
// and "frmId_3_date_year".
string FieldId { get; }
// the human readable field label
string Label { get; }
// some functionality may require knowledge of the
// Parent component. For example, a DayField with a value of "30"
// would need to ask its Parent, a CompositeDateField
// for its MonthField's value in order to validate
// that the month is not "February"
IFormComponent Parent { get; }
// Gets any child components or null if the
// component is a leaf component (has no children).
IList<IFormComponent> GetChildren();
// For leaf components, this method should accept the AttemptedValue from the value provider
// during Model Binding, and create the appropriate value.
// For composites, the input should be delimited in someway, and this method should parse the
// string to create the child components.
void BindTo(string value);
// This method should parse the Children or Underlying value to the
// default used by your business models. (e.g. a CompositeDateField would
// return a DateTime. You can get type safety by creating a FormComponent<TValue>
// which would help to avoid issues in binding.
object GetValue();
// This method would render the field to the http response stream.
// This makes it easy to render the forms simply by looping through
// the array. Implementations could extend this for using an injected
// formatting
void Render(TextWriter writer);
}
我假设可以通过某种可以作为表单参数包含的 id 访问自定义表单。有了这个假设，模型绑定器和提供者可能看起来像这样。
public interface IForm : IFormComponent
{
Guid FormId { get; }
void Add(IFormComponent component);
}
public interface IFormRepository
{
IForm GetForm(Guid id);
}
public class CustomFormModelBinder : IModelBinder
{
private readonly IFormRepository _repository;
public object BindModel(ControllerContext controllerContext, ModelBindingContext bindingContext)
{
ValueProviderResult result;
if(bindingContext.ValueProvider.TryGetValue("_customFormId", out result))
{
var form = _repository.GetForm(new Guid(result.AttemptedValue));
var fields = form.GetChildren();
// loop through the fields and bind their values
return form;
}
throw new Exception("Form ID not found.");
}
}
显然，这里的所有代码都只是为了说明问题，需要完成并清理以供实际使用。此外，即使完成，这也只会绑定到 IForm 接口的实现，而不是强类型业务对象。 （将其转换为字典并使用 Castle DictionaryAdapter 构建强类型代理并不是一个巨大的步骤，但由于您的用户正在网站上动态创建表单，因此您的解决方案中可能没有强类型模型，并且这无关紧要）。希望这有助于更多。