title: Design By Contract in C#3.0
body: <p>I know that C# 4.0 has the <code>Code Contract</code> feature that can be used to implement post-condition and pre-condition. But I am wanting to implement it using C# 3.0 only. I am experimenting to use this feature in my work. Is it possible to use <code>attributes</code> to implement post-conditions and pre-conditions? </p>
  
  <p>Any advise?</p>
  
  <p>Thanks.</p>