title: Seems like I'm missing a directive? System.Data.DataTableCollection does not contain a definition for 'First'
body: <p>I have a dataset where I'm running a foreach loop on the rows...</p>
  
  <pre><code>foreach(var row in input.Tables.First().Rows)
  {....
  </code></pre>
  
  <p>but I'm receiving this compilation error:</p>
  
  <blockquote>
    <p>Error 1   'System.Data.DataTableCollection' does not contain a definition for 'First' and no extension method 'First' accepting a first argument of type 'System.Data.DataTableCollection' could be found (are you missing a using directive or an assembly reference?)</p>
  </blockquote>
  
  <p>It almost seems like I'm missing a directive but I'm using System.Linq and I also have System.Data.DataSetExtensions added as a reference.</p>
  
  <p>What am I missing? Any help would be greatly appreciated. The project is set to .NET 4.5</p>