title: Verify one layer only
body: <p>I want to verify a variable holding json only has one level simple format. Can someone provide an example where only one level is verified - not a multi-level verification? </p>
  
  <pre><code>   &lt;?php
  $json = '{"a":1,"b":2,"c":3,"d":4,"e":5}';
  isValidOnlayer($json); // True
  $json = '{
      "id": "0001",
      "type": "donut",
      "name": "Cake",
      "ppu": 0.55,
      "batters":
          {
              "batter":
                  [
                      { "id": "1001", "type": "Regular" },
                      { "id": "1002", "type": "Chocolate" },
                      { "id": "1003", "type": "Blueberry" },
                      { "id": "1004", "type": "Devil's Food" }
                  ]
          },
      "topping":
          [
              { "id": "5001", "type": "None" },
              { "id": "5002", "type": "Glazed" },
              { "id": "5005", "type": "Sugar" },
              { "id": "5007", "type": "Powdered Sugar" },
              { "id": "5006", "type": "Chocolate with Sprinkles" },
              { "id": "5003", "type": "Chocolate" },
              { "id": "5004", "type": "Maple" }
          ]
      }'
      isValidOnlayer($json); // False
  ?&gt;
  </code></pre>