How do I change string to hash object in Javascript? [duplicate]

Your string is not proper, JSON parser will never parse it properly. Here you can't use eval() function approach. It's not like an Array but a HashMap or simply malformed Object. In your case, You need json with key-value pair combination.

{'lat': -37.819616, 'lng': 144.968119},
{'lat': -38.330766, 'lng': 144.695692}

If Your Object does not contains child objects/arrays you can use the following code.

function formatJSON2Array (str) {
    var arr = [];
    str = str.replace(/^\{|\}$/g,'').split(',');
    for(var i=0,cur,pair;cur=str[i];i++){
        arr[i] = {};
        pair = cur.split(':');
        arr[i][pair[0]] = /^\d*$/.test(pair[1]) ? +pair[1] : pair[1];
    }
  console.log("JSON Array>>> " +JSON.stringify(arr)); // it will print [{"a":12},{"b":"c"},{"foo":"bar"}] in console
    return arr;
}

formatJSON2Array("{lat: -37.819616, lng: 144.968119},{lat: -38.330766, lng: 144.695692}");

Above code will convert your entered string into Array of objects.

If however you actually wanted a HashMap (Associative Array) and NOT an array, use the following code:

function FormatJSON2Object(str) {
    var obj = {};
    str = str.replace(/^\{|\}$/g,'').split(',');
    for(var i=0,cur,pair;cur=str[i];i++){
        pair = cur.split(':');
        obj[pair[0]] = /^\d*$/.test(pair[1]) ? +pair[1] : pair[1];
    }
  console.log("JSON Object >>> "+ JSON.stringify(obj)); // it will return {"lat":" -37.819616"," lng":" 144.695692","{lat":" -38.330766"}
    return obj;
}

FormatJSON2Object("{lat: -37.819616, lng: 144.968119},{lat: -38.330766, lng: 144.695692}");

Please note that, above code will become a lot more complex when you start nesting objects and arrays with it. This thread helped me a lot for this JSON conversions with array-objects and parsing. If you have any key value pair except lat lng, it will work fine.

This simple line should do it (and work with nested values if need be):

JSON.parse('[' + string.replace(/(\w+)\s*:/g, '"$1":') + ']')

Test it here:

let string = `
  {lat: -37.819616, lng: 144.968119},
  {lat: -38.330766, lng: 144.695692},
  {lat: -39.927193, lng: 175.053218},
  {lat: -41.330162, lng: 174.865694},
  {lat: -42.734358, lng: 147.439506},
  {lat: -42.734358, lng: 147.501315},
  {lat: -42.735258, lng: 147.438000},
  {lat: -43.999792, lng: 170.463352}`;

let result = JSON.parse('[' + string.replace(/(\w+)\s*:/g, '"$1":') + ']');

console.log(result);

JSON.parse("{\"a\":\"b\"}")

{ a: 'b' }