title: Sort a sorted object array based on ascending order of another attribute
body: <p>I have an array of objects having attributes <code>TechType</code> and <code>ProductName</code>. The given array is already sorted by <code>TechType</code> (not necessarily alphabetically); now within this sorted array, it has to be further sorted by ascending order based on <code>ProductName</code>.</p>
  
  <pre><code>var products= [
      {
          "TechType": "ADSL",
          "ProductName": " Zen ADSL Services",
              }, {
          "TechType": "ADSL",
          "ProductName": "ADSL Services",
              }, {
          "TechType": "T1",
          "ProductName": "T1-Voice",
  },{
        "TechType": "T1",
          "ProductName": " Aviate T1-Voice",
  
  
   }
  ];
  </code></pre>
  
  <p>The sorted array should be </p>
  
  <pre><code>  var products= [
          {
              "TechType": "ADSL",
              "ProductName": " ADSL Services",
                  }, {
              "TechType": "ADSL",
              "ProductName": "Zen ADSL Services",
                  }, {
              "TechType": "T1",
              "ProductName": " Aviate T1-Voice",
      },{
            "TechType": "T1",
              "ProductName": " T1-Voice",
  
  
       }
      ];
  </code></pre>