如何单元测试自定义的ModelBinder？
这是代码。
public class MagicBinder : DefaultModelBinder
{
public override object BindModel(ControllerContext controllerContext,ModelBindingContext bindingContext)
{
var boundModelObject = base.BindModel(controllerContext,bindingContext);
var properties = bindingContext.ModelType.GetProperties().Where(a => a.CanWrite);
foreach (var propertyInfo in properties)
{
object outValue = null;
bindingContext.TryGetValue(propertyInfo.Name,propertyInfo.DeclaringType,out outValue);
propertyInfo.SetValue(boundModelObject,outValue,null);
}
return boundModelObject;
}
}
这里是测试脚本。
[TestMethod]
public void TestFooBinding()
{
var dict = new ValueProviderDictionary(null)
{
{"Number",new ValueProviderResult("2","2",null)},{"Test",new ValueProviderResult("12","12",};
var bindingContext = new ModelBindingContext() { ModelName = "foo",ValueProvider = dict};
var target = new MagicBinder();
Foo result = (Foo)target.BindModel(null,bindingContext);
}
public class Foo
{
public int Number { get; set; }
public int Test { get; set; }
}
问题？在MagicBinder中，bindingContext.Model为null。如果我尝试设置它
bindingContext.Model = new Foo()。我得到一个例外，称它已被弃用，我应该设置ModelMetadata。
那么如何构建ModelMetadata？它甚至不能被嘲笑。
解决方法
尝试这样：
[TestMethod]
public void TestFooBinding()
{
// arrange
var formCollection = new NameValueCollection
{
{ "Number","2" },{ "Test","12" },};
var valueProvider = new NameValueCollectionValueProvider(formCollection,null);
var Metadata = ModelMetadataProviders.Current.GetMetadataForType(null,typeof(Foo));
var bindingContext = new ModelBindingContext
{
ModelName = "",ValueProvider = valueProvider,ModelMetadata = Metadata
};
var controllerContext = new ControllerContext();
var sut = new MagicBinder();
// act
Foo actual = (Foo)sut.BindModel(controllerContext,bindingContext);
// assert
// TODO:
}
