如何为[FromQuery]对象Asp.Net核心ModelBinding使用DataMember名称

Question

对于[FromBody]参数，我可以使用DataMember.Name来设置属性的自定义名称，但它不适用于[FromQuery]。我想这取决于模型绑定

我想处理类似?status=a&status=b&status=c的查询

带有查询对象[FromQuery]MyQuery

[DataContract]
class MyQuery {
[DataMember(Name = "status")
public IReadOnlyList<string> Statuses { get; set; }
}

我可以像一样做

class MyQuery {
[FromQuery("status")
public IReadOnlyList<string> Statuses { get; set; }
}

但我想避免AspNetCore对模型的依赖，有什么解决方案吗？

(关于Web API 2也有类似的问题，但它没有回答(

Answer 1

我没有找到使用标准属性的方法，所以我使用statuses名称，为字符串集合使用自定义属性

[AttributeUsage(AttributeTargets.Field | AttributeTargets.Property, AllowMultiple = false, Inherited = true)]
internal class StringCollectionAttribute : Attribute
{
}

并使用自定义模型绑定

public class StringCollectionBinderProvider : IModelBinderProvider
{
private static readonly Type BinderType = typeof(StringCollectionBinder);
private static readonly Type ModelType = typeof(List<string>);
public IModelBinder GetBinder(ModelBinderProviderContext context)
{
if (context == null)
{
throw new ArgumentNullException(nameof(context));
}
var propertyAttributes = (context.Metadata as DefaultModelMetadata)?.Attributes.PropertyAttributes;
var isStringCollection =
propertyAttributes?.Any(x => x is StringCollectionAttribute) == true
&& context.Metadata.ModelType.IsAssignableFrom(ModelType);
return isStringCollection ? new BinderTypeModelBinder(BinderType) : null;
}
}
public class StringCollectionBinder : IModelBinder
{
private const char ValueSeparator = ',';
public Task BindModelAsync(ModelBindingContext bindingContext)
{
if (bindingContext == null)
{
throw new ArgumentNullException(nameof(bindingContext));
}
var modelName = bindingContext.ModelName;
var valueCollection = bindingContext.ValueProvider.GetValue(modelName);
if (valueCollection == ValueProviderResult.None)
{
return Task.CompletedTask;
}
bindingContext.ModelState.SetModelValue(modelName, valueCollection);
var stringCollection = valueCollection.FirstValue;
if (string.IsNullOrEmpty(stringCollection))
{
return Task.CompletedTask;
}
var collection = stringCollection.Split(ValueSeparator).ToList();
bindingContext.Result = ModelBindingResult.Success(collection);
return Task.CompletedTask;
}
}