There's a lot of difference between a C# property and attribute. A
property lets you get/set data in your class. However, an attribute
allows you to decorate elements of your code with declarative
information. i.e. here's a class with three properties:
public class Customer
{
public string Name { get; set; }
public string Email { get; set; }
public string Address { get; set; }
}
and you use it like this:
var cust = new Customer();
cust.Name = "Some Name";
Console.WriteLine("Name: " + cust.Name);
However,
an attribute is much different and the attributes you use depend on the
tool you are using. For example, if you had a method you wanted to
deprecate from your application, you could use the Obsolete attribute
like this:
[Obsolete("Method deprecated - Please use MethB instead")]
public void MethA() { ... }
If you were writing unit tests in VS2008, you would use Test and TestMethod attributes like this:
[Test]
public class MyTestClass
{
[TestMethod]
public void MyTestMethod() { .... }
}
To
summarize, attributes support tools that operate on your code, but
properties define the state of an object and there is no logical
comparison between the two.
Because of this difference in purpose
and the fact that you asked a question that sounds like you feel they
are similar, I wonder what you meant by the term "attribute". It almost
sounds like you were really wanting to know the difference between
fields and properties. Just in case, that was really your question: a
field gives calling code direct access to the data in your class, but a
property allows you to control access to that value. If the underlying
representation of the data changes, then a field would cause calling
code to break, which could cause a rippling effect through your code for
trying to fix the change. If someone else's code depends on that
field, then their code would break, which means that you might not be
able to change your class. If you use a property, you can manipulate
the representation of the data in the property accessors if there ever
was a change and calling code would never know, which gives you more
maintainable code. For this reason, I tend to use properties as a
general preference over fields. I won't go as far as to suggest that
you should never use a *public* field, because someone might have a
valid use case for it (in a limited scenario), but I still think that
for general software development the property will serve you better.
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