UnitTest_Csharp_Attributes_Test_Read_Attributes.cs

[Fact]
public void Test_Read_Attributes()
{
    //get the Product-class
    var type = typeof(Product);

    //Get the attributes of the Product-class and we are expecting the [Serializable]
    var attribute = (SerializableAttribute)type.
                    GetCustomAttributes(typeof(SerializableAttribute), false).FirstOrDefault();

    Assert.NotNull(attribute);

    //Check if [Serializable] has been read.
    //Let's check if the type of the attribute is as expected
    Assert.IsType<SerializableAttribute>(attribute);

    //Let's get only those 2 methods that we have declared 
    //and ignore the special names (these are the auto-generated setter/getter)
    var methods = type.GetMethods(BindingFlags.Instance | 
                                  BindingFlags.Public | 
                                  BindingFlags.DeclaredOnly)
                       .Where(method => !method.IsSpecialName).ToArray();

    //Check if the product-class has two methods 
    //Let's check if the Product-class has two methods.
    Assert.True(methods.Length == 2);

    Assert.True(methods[0].Name == "GetProductFullName");
    Assert.True(methods[1].Name == "RunOnlyOnDebugMode");

    //Check if each methods does have attributes. 
    Assert.True(methods.All( method =>method.GetCustomAttributes(false).Length ==1));

    //Let's get the first method and its attribute. 
    var obsoleteAttribute = methods[0].GetCustomAttribute<ObsoleteAttribute>();

    // Check if the method GetProudctFullName is using the Obsolete attributes. 
    Assert.IsType<ObsoleteAttribute>(obsoleteAttribute);

    //Let's get the second method and its attribute. 
    var conditionalAttribute = methods[1].GetCustomAttribute<ConditionalAttribute>();

    //Check if the method RunOnlyOnDebugMode is using the Conditional attributes.
    Assert.IsType<ConditionalAttribute>(conditionalAttribute);
}