How to create and empty JSON in JavaScript and add keys and additional JSON objects dynamically?-CodePudding

How to create and empty JSON in JavaScript and add keys and additional JSON objects dynamically?

mydata = {}

newdata = {
       'first': [ {'1': 'test'} ]
}

I tried this

<!DOCTYPE html>
<html>
<body>

<p id="demo"></p>

<script>
const myJSON = '{}';
myJSON['first']['1'] = 'test';
const myObj = JSON.parse(myJSON);

let text = "";
for (const x in myObj) {
  text  = x   ", ";
}
document.getElementById("demo").innerHTML = text;
</script>

</body>
</html>

CodePudding user response：

Parse the json into an object, then set his properties

const myJSON = '{}';
const myObj = JSON.parse(myJSON);
myObj['first'] = [{'1':'test'}];

console.log(myObj);
newdata = {
       'first': [ {'1': 'test'} ]
}

CodePudding user response：

try this

var newData = { first: [{ 1: "test" }] };

//or 

const myJson = {};
myJson["first"]= [];
var newItem={ "1": "test" };
myJson["first"].push(newItem);
myJson["second"]= [];
newItem={ "2": "test" };
myJson["second"].push(newItem);

console.log(JSON.stringify(myJson));