title: How to join two datasource which return all rows and group by condition?
body: <p>I have a problem when using LINQ to join two datasource. Two datasource created by a query like :</p>
  
  <p>var A = (from....
           group .... into grp
           select new
           {
              Qty = grp.Count(),
              Code = grp.Key.Code,
              Name = grp.Key.Name
           });</p>
  
  <p>var B = (from....
           group .... into grp
           select new
           {
              Qty = grp.Count(),
              Code = grp.Key.ContCode,
              Name = grp.Key.ContName
           });</p>
  
  <p>Value of 'A' will be returned like this :</p>
  
  <pre><code>    Qty-Code-Name
  
      1-10A-Cont10
      1-20B-Cont20
      1-30C-Cont30 
  </code></pre>
  
  <p>Value of 'B' will be returned like this :</p>
  
  <pre><code>    Qty-Code-Name
  
      1-10A-Cont10
      1-20B-Cont20
      1-30C-Cont30
      1-40D-Cont40
      1-50E-Cont50
  </code></pre>
  
  <p>I want to join A and B (or do somethings) and the result like this (which sum column 'Qty' if they have the same 'Code' and 'Name') :</p>
  
  <pre><code>    Qty-Code-Name
  
      2-10A-Cont10
      2-20B-Cont20
      2-30C-Cont30
      1-40D-Cont40
      1-50E-Cont50
  </code></pre>
  
  <p>How can I do it ? Please help me.
  Thank you very much !</p>