JSFiddle - React, Tailwind, and code Playground

JavaScript

// Thanks to: http://stackoverflow.com/a/3710226/2010246
function IsJsonString(str) {
    try {
        JSON.parse(str);
    } catch (e) {
        return false;
    }
    return true;
}

// And http://stackoverflow.com/a/22482737/2010246
function isObject(val) {
    if (val === null) { return false;}
    return ( (typeof val === 'function') || (typeof val === 'object') );
}

var Json = "[[0,1],[1,2],[2,3]]"; // in chart: [[x=0,y=1],[x=1,y=2],[x=2,y=3]]
var isCorrect = IsJsonString(Json);

console.log('a JSON string: ' + Json);
console.log('is this correct JSON: ' + isCorrect);
console.log('can I use it? ' + isObject(Json));

// Fix time
Json=JSON.parse(Json);
console.log('can I use it now? ' + isObject(Json));