title: Merge array with underscore by keys
body: <p>I have 2 arrays : </p>
  
  <pre><code>[{id:1,name:"name"},{id:2,name:"name2"} ,{id:3,name:"name3"}]
  
  [{id:1,date:"123"},{id:2,date:"456"}]
  </code></pre>
  
  <p>Array 1 should be updated only if the id is equal :
  So the array 1 will looks like</p>
  
  <p>It should not create a new array . Only update the array 1 based on array 2</p>
  
  <pre><code>[{id:1,name:"name",date:"123"},{id:2,name:"name2",date:"456"} ,{id:3,name:"name3"}]
  </code></pre>
  
  <p>I managed to do that with for loop on <code>array2</code> and inside the for filter like the following : </p>
  
  <pre><code>._filter(array1,function(item){
   If(item.id=array2.id)
      Do smth and update the array1.date
  })
  </code></pre>
  
  <p>How do I doing that in he best way ? Using underscore.js</p>