asp.net-mvc-4 - ASP.NET Web API - 模型绑定(bind)器

Question

我需要使用某种自定义模型绑定(bind)器来始终以英国格式处理传入日期，我已经设置了自定义模型绑定(bind)器并像这样注册:

GlobalConfiguration.Configuration.BindParameter(typeof(DateTime), new DateTimeModelBinder());

这似乎只适用于查询字符串参数，并且只有在我像这样在参数上指定 [ModelBinder] 时才有效，有没有办法让所有操作都使用我的模型绑定(bind)器:

public IList<LeadsLeadRowViewModel> Get([ModelBinder]LeadsIndexViewModel inputModel)

另外，如何将我发布的表单发送到我的 Api Controller 以使用我的模型绑定(bind)器？

Answer 1

您可以通过实现 ModelBinderProvider 并将其插入到服务列表中来全局注册模型绑定(bind)器。

Global.asax 中的使用示例:

GlobalConfiguration.Configuration.Services.Insert(typeof(ModelBinderProvider), 0, new Core.Api.ModelBinders.DateTimeModelBinderProvider());

下面是演示 ModelBinderProvider 和 ModelProvider 实现的示例代码，它们以文化感知方式(使用当前线程文化)转换 DateTime 参数；

DateTimeModelBinderProvider 实现:

using System;
using System.Web.Http;
using System.Web.Http.ModelBinding;

...

public class DateTimeModelBinderProvider : ModelBinderProvider
{
    readonly DateTimeModelBinder binder = new DateTimeModelBinder();

    public override IModelBinder GetBinder(HttpConfiguration configuration, Type modelType)
    {
        if (DateTimeModelBinder.CanBindType(modelType))
        {
            return binder;
        }

        return null; 
    }
}

DateTimeModelBinder 实现:

public class DateTimeModelBinder : IModelBinder
{
    public bool BindModel(HttpActionContext actionContext, ModelBindingContext bindingContext)
    {
        ValidateBindingContext(bindingContext);

        if (!bindingContext.ValueProvider.ContainsPrefix(bindingContext.ModelName) ||
            !CanBindType(bindingContext.ModelType))
        {
            return false;
        }

        bindingContext.Model = bindingContext.ValueProvider
            .GetValue(bindingContext.ModelName)
            .ConvertTo(bindingContext.ModelType, Thread.CurrentThread.CurrentCulture);

        bindingContext.ValidationNode.ValidateAllProperties = true;

        return true;
    }

    private static void ValidateBindingContext(ModelBindingContext bindingContext)
    {
        if (bindingContext == null)
        {
            throw new ArgumentNullException("bindingContext");
        }

        if (bindingContext.ModelMetadata == null)
        {
            throw new ArgumentException("ModelMetadata cannot be null", "bindingContext");
        }
    }

    public static bool CanBindType(Type modelType)
    {
        return modelType == typeof(DateTime) || modelType == typeof(DateTime?);
    }
}