2

我正在创建一个自定义模型绑定器，以在使用传入值更新模型之前从数据库中加载模型。（继承自 DefaultModelBinder）

我需要重写哪种方法才能做到这一点？

4

2 回答 2

3

您需要重写 DefaultModelBinder 基类的 BindModel 方法：

    public override object BindModel(ControllerContext controllerContext, ModelBindingContext bindingContext)
    {
        if (bindingContext.ModelType == typeof(YourType))
        {
            var instanceOfYourType = ...; 
            // load YourType from DB etc..

            var newBindingContext = new ModelBindingContext
            {
                ModelMetadata = ModelMetadataProviders.Current.GetMetadataForType(() => instanceOfYourType, typeof(YourType)),
                ModelState = bindingContext.ModelState,
                FallbackToEmptyPrefix = bindingContext.FallbackToEmptyPrefix,
                ModelName = bindingContext.FallbackToEmptyPrefix ? string.Empty : bindingContext.ModelName,
                ValueProvider = bindingContext.ValueProvider,
            };
            if (base.OnModelUpdating(controllerContext, newBindingContext)) // start loading..
            {
                // bind all properties:
                base.BindProperty(controllerContext, bindingContext, TypeDescriptor.GetProperties(typeof(YourType)).Find("Property1", false));
                base.BindProperty(controllerContext, bindingContext, TypeDescriptor.GetProperties(typeof(YourType)).Find("Property2", false));

                // trigger the validators:
                base.OnModelUpdated(controllerContext, newBindingContext);
            }

            return instanceOfYourType;
        }            
        throw new InvalidOperationException("Supports only YourType objects");
    }
于 2011-06-01T20:56:35.517 回答
0

您需要重写BindModel来执行此操作。

于 2011-06-01T20:54:32.067 回答