How to get all key in JSON object (javascript)

Question

{\"document\":
  {\"people\":[
    {\"name\":[\"Harry Potter\"],\"age\":[\"18\"],\"gender\":[\"Male\"]},
    {\"name\":[\"hermione granger\"],\"age\":[\"18\"],\"gend         


        

Answer 1

var input = {"document":
  {"people":[
    {"name":["Harry Potter"],"age":["18"],"gender":["Male"]},
    {"name":["hermione granger"],"age":["18"],"gender":["Female"]},
  ]}
}

var keys = [];
for(var i = 0;i