public void IsPreviousPageButtonEnableTest()
{
CustomerFormPresentationModel model = new CustomerFormPresentationModel(new Model());
PrivateObject target = new PrivateObject(model);
List <CategoryState> categoryState = (List <CategoryState>)target.GetFieldOrProperty("_categoriesState");
categoryState[0].CurrentPage = 1;
Assert.IsFalse(model.IsPreviousPageButtonEnable("漢堡"));
categoryState[0].CurrentPage = 2;
Assert.IsTrue(model.IsPreviousPageButtonEnable("漢堡"));
Assert.IsFalse(model.IsPreviousPageButtonEnable("找不到"));
}