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String to object in JS

Posted by: admin November 29, 2017 Leave a comment

Questions:

I have a string as

string = "firstName:name1, lastName:last1"; 

now I need one object obj such that

obj = {firstName:name1, lastName:last1}

How can I do this in JS?

Answers:

Actually, the best solution is using JSON:

Documentation

JSON.parse(text[, reviver]);

Examples:

1)

var myobj = JSON.parse('{ "hello":"world" }');
alert(myobj.hello); // 'world'

2)

var myobj = JSON.parse(JSON.stringify({
    hello: "world"
});
alert(myobj.hello); // 'world'

3)
Passing a function to JSON

var obj = {
    hello: "World",
    sayHello: (function() {
        console.log("I say Hello!");
    }).toString()
};
var myobj = JSON.parse(JSON.stringify(obj));
myobj.sayHello = new Function("return ("+myobj.sayHello+")")();
myobj.sayHello();

Questions:
Answers:

Your string looks like a JSON string without the curly braces.

This should work then:

obj = eval('({' + str + '})');

Questions:
Answers:

If I’m understanding correctly:

var properties = string.split(', ');
var obj = {};
properties.forEach(function(property) {
    var tup = property.split(':');
    obj[tup[0]] = tup[1];
});

I’m assuming that the property name is to the left of the colon and the string value that it takes on is to the right.

Note that Array.forEach is JavaScript 1.6 — you may want to use a toolkit for maximum compatibility.

Questions:
Answers:

This simple way…

var string = "{firstName:'name1', lastName:'last1'}";
eval('var obj='+string);
alert(obj.firstName);

output

name1

Questions:
Answers:

if you’re using JQuery:

var obj = jQuery.parseJSON('{"path":"/img/filename.jpg"}');
console.log(obj.path); // will print /img/filename.jpg

REMEMBER: eval is evil! 😀

Questions:
Answers:

I implemented a solution in a few lines of code which works quite reliably.

Having an HTML element like this where I want to pass custom options:

<div class="my-element"
    data-options="background-color: #dadada; custom-key: custom-value;">
</div>

a function parses the custom options and return an object to use that somewhere:

function readCustomOptions($elem){
    var i, len, option, options, optionsObject = {};

    options = $elem.data('options');
    options = (options || '').replace(/\s/g,'').split(';');
    for (i = 0, len = options.length - 1; i < len; i++){
        option = options[i].split(':');
        optionsObject[option[0]] = option[1];
    }
    return optionsObject;
}

console.log(readCustomOptions($('.my-element')));

Questions:
Answers:
string = "firstName:name1, lastName:last1";

This will work:

var fields = string.split(', '),
    fieldObject = {};

if( typeof fields === 'object') ){
   fields.each(function(field) {
      var c = property.split(':');
      fieldObject[c[0]] = c[1];
   });
}

However it’s not efficient. What happens when you have something like this:

string = "firstName:name1, lastName:last1, profileUrl:http://localhost/site/profile/1";

split() will split ‘http’. So i suggest you use a special delimiter like pipe

 string = "firstName|name1, lastName|last1";


   var fields = string.split(', '),
        fieldObject = {};

    if( typeof fields === 'object') ){
       fields.each(function(field) {
          var c = property.split('|');
          fieldObject[c[0]] = c[1];
       });
    }

Questions:
Answers:

This is universal code , no matter how your input is long but in same schema if there is : separator 🙂

var string = "firstName:name1, lastName:last1"; 
var pass = string.replace(',',':');
var arr = pass.split(':');
var empty = {};
arr.forEach(function(el,i){
  var b = i + 1, c = b/2, e = c.toString();
     if(e.indexOf('.') != -1 ) {
     empty[el] = arr[i+1];
  } 
}); 
  console.log(empty)

Questions:
Answers:

If you have a string like foo: 1, bar: 2 you can convert it to a valid obj with:

str
  .split(',')
  .map(x => x.split(':').map(y => y.trim()))
  .reduce((a, x) => {
    a[x[0]] = x[1];
    return a;
  }, {});

Thanks to niggler in #javascript for that.

Questions:
Answers:
var stringExample = "firstName:name1, lastName:last1 | firstName:name2, lastName:last2";    

var initial_arr_objects = stringExample.split("|");
    var objects =[];
    initial_arr_objects.map((e) => {
          var string = e;
          var fields = string.split(','),fieldObject = {};
        if( typeof fields === 'object') {
           fields.forEach(function(field) {
              var c = field.split(':');
              fieldObject[c[0]] = c[1]; //use parseInt if integer wanted
           });
        }
            console.log(fieldObject)
            objects.push(fieldObject);
        });

“objects” array will have all the objects

Questions:
Answers:

In your case

var KeyVal = string.split(", ");
var obj = {};
var i;
for (i in KeyVal) {
    KeyVal[i] = KeyVal[i].split(":");
    obj[eval(KeyVal[i][0])] = eval(KeyVal[i][1]);
}