How to convert 1 to true or 0 to false upon model fetch

I have a model that is set with a JSON response from a mysql database. The model data is set with true or false into a boolean/tinyint field in the database, which uses 1 or 0.

In my view, I have a binding that checks for a boolean with underscore's _.isBoolean. Of course, when my model receives the data, it is set with 1 or 0 instead of true or false and the _.isBoolean check fails.

Is there anyway to either correctly have my JSON response from mysql be a boolean true or false value instead of 1 or 0, or preferably, is there a way to have my model update itself upon fetch (and before the view renders) to cast true or false based on it's 1 or 0 property?

e.g. my model's data looks like {"isChecked":"1"} when I need it to be {"isChecked":true}

Thank you greatly for any suggestions you may have!

All you need is convert string to int with + and convert the result to boolean with !!:

var response = {"isChecked":"1"};
response.isChecked = !!+response.isChecked

You can do this manipulation in the parse method:

parse: function (response) {
  response.isChecked = !!+response.isChecked;
  return response;
}

UPDATE: 7 years later, I find Number(string) conversion more elegant. Also mutating an object is not the best idea. That being said:

parse: function (response) {
  return Object.assign({}, response, {
    isChecked: !!Number(response.isChecked), // OR
    isChecked: Boolean(Number(response.isChecked))
  });
}

Use a double not:

!!1 = true;

!!0 = false;

obj.isChecked = !!parseInt(obj.isChecked);

Here's another option that's longer but may be more readable:

Boolean(Number("0")); // false
Boolean(Number("1")); // true

Assigning Comparison to property value

JavaScript

You could assign the comparison of the property to "1"

obj["isChecked"] = (obj["isChecked"]==="1");

This only evaluates for a String value of "1" though. Other variables evaulate to false like an actual typeof number would be false. (i.e. obj["isChecked"]=1)

If you wanted to be indiscrimate about "1" or 1, you could use:

obj["isChecked"] = (obj["isChecked"]=="1");

Example Outputs

console.log(obj["isChecked"]==="1"); // true
console.log(obj["isChecked"]===1); // false
console.log(obj["isChecked"]==1); // true
console.log(obj["isChecked"]==="0"); // false
console.log(obj["isChecked"]==="Elephant"); // false

PHP

Same concept in PHP

$obj["isChecked"] = ($obj["isChecked"] == "1");

The same operator limitations as stated above for JavaScript apply.

Double Not

The 'double not' also works. It's confusing when people first read it but it works in both languages for integer/number type values. It however does not work in JavaScript for string type values as they always evaluate to true:

JavaScript

!!"1"; //true
!!"0"; //true
!!1; //true
!!0; //false
!!parseInt("0",10); // false

PHP

echo !!"1"; //true
echo !!"0"; //false
echo !!1; //true
echo !!0; //false

Boolean(Number(myVar))

or

!!+myVar