我创建一个视图模型自定义模型绑定,实现IModelBinder
我在我的视图模型有很多的属性,其中大部分不需要任何自定义绑定。而不是明确地将所有的属性值对我的模型分别从ModelBindingContext
,我会能够得到的框架为我的模型绑定,那么我会进行任何自定义绑定:
public class ApplicationViewModelBinder : IModelBinder
{
public Task BindModelAsync(ModelBindingContext bindingContext)
{
if (bindingContext == null)
{
throw new ArgumentNullException(nameof(bindingContext));
}
// get .net core to bind values on model
// Cary out any customization of the models properties
bindingContext.Result = ModelBindingResult.Success(bindingContext.Model);
return Task.CompletedTask;
}
}
基本上我想进行默认模型绑定,然后应用自定义绑定,类似于本SO post但对于.NET的核心,而不是框架所采取的做法。
我认为应用默认绑定是直截了当的,但一直没能找出如何做到这一点。我相信该解决方案将涉及ComplexTypeModelBinder
和ComplexTypeModelBinderProvider
类,但似乎无法找出如何去做。
我知道我可以只进行任何更改时POST请求打我控制器的方法,但这似乎错误的地点和错误的时间这样做。
对于自定义ComplexTypeModelBinder
,你可以从ComplexTypeModelBinder
继承。
public class BinderModel
{
public int Id { get; set; }
public string Name { get; set; }
public string BinderValue { get; set; }
}
[HttpPost]
public void Post([FromForm]BinderModel value)
{
}
public class CustomBinder : ComplexTypeModelBinder
{
private readonly IDictionary<ModelMetadata, IModelBinder> _propertyBinders;
public CustomBinder(IDictionary<ModelMetadata, IModelBinder> propertyBinders)
: base(propertyBinders)
{
_propertyBinders = propertyBinders;
}
protected override Task BindProperty(ModelBindingContext bindingContext)
{
if (bindingContext.FieldName == "BinderValue")
{
bindingContext.Result = ModelBindingResult.Success("BinderValueTest");
return Task.CompletedTask;
}
else
{
return base.BindProperty(bindingContext);
}
}
protected override void SetProperty(ModelBindingContext bindingContext, string modelName, ModelMetadata propertyMetadata, ModelBindingResult result)
{
base.SetProperty(bindingContext, modelName, propertyMetadata, result);
}
}
public class CustomBinderProvider : IModelBinderProvider
{
public IModelBinder GetBinder(ModelBinderProviderContext context)
{
if (context == null)
{
throw new ArgumentNullException(nameof(context));
}
if (context.Metadata.IsComplexType && !context.Metadata.IsCollectionType)
{
var propertyBinders = new Dictionary<ModelMetadata, IModelBinder>();
for (var i = 0; i < context.Metadata.Properties.Count; i++)
{
var property = context.Metadata.Properties[i];
propertyBinders.Add(property, context.CreateBinder(property));
}
//var loggerFactory = context.Services.GetRequiredService<ILoggerFactory>();
//return new ComplexTypeModelBinder(propertyBinders, loggerFactory);
return new CustomBinder(propertyBinders);
}
return null;
}
}
public void ConfigureServices(IServiceCollection services)
{
services.AddMvc(options => {
options.ModelBinderProviders.Insert(0, new CustomBinderProvider());
});
}