1// To convert a boolean to a string we use the .toString() method
2let isValid = true;
3
4console.log(isValid.toString()); // outputs "true"
5console.log(isValid); // outputs true
6

1let bool = "True";
2JSON.parse(bool.toLowerCase());

1var myBool = Boolean("false");  // == true
2
3var myBool = !!"false";  // == true

1let toBool = string => string === 'true' ? true : false;
2// Not everyone gets ES6 so here for the beginners
3function toBool(string){
4	if(string === 'true'){
5      return true;
6    } else {
7      return false;
8    }
9}

1stringToBoolean: function(string){
2    switch(string.toLowerCase().trim()){
3        case "true": case "yes": case "1": return true;
4        case "false": case "no": case "0": case null: return false;
5        default: return Boolean(string);
6    }
7}

1const stringBools = [
2  'true',
3  'false',
4  'asdf'
5];
6const bools = [];
7
8for (const i = 0; i < stringBools.length; i++) {
9  const stringBool = stringBools[i];
10  if (stringBool == true) {
11    bools.push(true);
12  } else if (stringBool == false) {
13    bools.push(false);
14  } else {
15    bools.push(null /* Change if you like */);
16  }
17}