How to set defined values for a parameter in C#?
<p>How can I set defined values for a parameter? I mean, for example, I have the following function:</p>

<pre><code>int functionA(string parameterA) {}
</code></pre>

<p>Now, when I call this function and input value for the parameterA, I want the value to be in the value set I have defined. For example, the defined value set is:</p>

<pre><code>string[] definedParameterA = { "Hello World", "stackoverflow" };
</code></pre>

<p>the value of parameterA I input must be "Hello World" or "stackoverflow".</p>
