Чтобы добавить новый элемент в JSON Object, просто используйте: jsonObject.key = value;
// your Example
var myObj = {
"data": [0,1,2,3,4,5,6,7],
"name":"number"
};
console.log(myObj);
// {"data": [0,1,2,3,4,5,6,7],
// "name":"number"}
myObj.myArray = ["a","b","c"];
console.log(myObj);
// {"data": [0,1,2,3,4,5,6,7],
// "name":"number",
// "myArray":["a","b","c"]}