title: Join 2 json objects to 1 in Angular 4-6
body: <p>I have two jsons:</p>
  
  <p>First (length 200):</p>
  
  <p>{date_end: "2099-12-31", id: "2341"}</p>
  
  <p>{date_end: "2099-12-31" id: "2342"}
  ...</p>
  
  <p>Second (length 200):</p>
  
  <p>{type: "free", discount:"none", warranty: "yes"}</p>
  
  <p>{type: "free", discount:"none", warranty: "no"}</p>
  
  <p>...</p>
  
  <p>How to join them to: </p>
  
  <p>{date_end: "2099-12-31", id: "2341", type: "free", discount:"none", warranty: "yes"}</p>
  
  <p>{date_end: "2099-12-31" id: "2342", type: "free", discount:"none", warranty: "no"}</p>
  
  <p>...</p>
  
  <p>I tried Object.assign but nothing happend. No result :( pls, help.</p>
  
  <p>Thanks for help! </p>