title: Express one dimension of 2d array as new array
body: <p>I have a 2d array <code>a[3,3]</code>. How can I express one dimension as a new array and pass it to some function?</p>
  
  <pre><code>int[,] a = new int[3,3];
  
  a[0,0] = 1;
  
  ...
  
  string b = concatenate(a[0]);     // where concatenate is a function
                                    // take a one dimension array as param
  </code></pre>
  
  <p>Also, can I create a 65000x65000 array with C#? I got some "out of memory" error.</p>