title: How to group by and sum for every 7 days using linq lambda?
body: <p>I have a filtered list of results for particular month. I am working on report that should print this in excel. How to query so that I display the results in this format?
  Expected format:</p>
  
  <pre><code>Date    Qty  Other fields
  1
  2
  3
  4
  5
  6
  7
  Total
  
  8
  9
  10
  11
  12
  13
  14
  Total
  ...
  29
  30
  31
  Total
  </code></pre>
  
  <p>I need to group by using lambda expression. Note: not all days of the filtered month have returned results, but I need to display all days anyway.</p>