Javascript - How do I declare a variable with the variable name based on a string?

Question

var cur_storage_unit = $('#storage_unit').val();

$('.size_unit').change(function() {
    var id = $(this).attr('id');

    //This is how I want it to work, but not sure how
    'cur_' + id = $(this).val();
});

The user 'changes' a of class 'size_unit' and id of 'storage_unit'. I want to then set the value of 'cur_storage_unit' to the new value of 'storage_unit'. In italics is how I want it to work, but I'm not sure the syntax of how to get it to work. Thanks!

Answer 1

you can create a new property on an object using a string as a key

var myObj = {};
myObj['cur_'+id] = $(this).val();

so in your case you would want an object with a known name where you can add dynamically named properties.

Answer 2

If it's global you can do window['cur_'+id];

Answer 3

You're probably better off using an Object, and storing it in there.

var cur_storage_unit = $('#storage_unit').val();

var values = {};  // storage for multiple values

$('.size_unit').change(function() {
    var id = this.id;

    values['cur_' + id] = this.value;  // store this value in the "values" object
});

// Accessible via values object
alert( values["cur_theid"] );