Arrays in JavaScript don’t use strings as keys. You will probably find that the value is there, but the key is an integer.
If you make Dict into an object, this will work:
var dict = {};
var addPair = function (myKey, myValue) {
dict[myKey] = myValue;
};
var giveValue = function (myKey) {
return dict[myKey];
};
The myKey variable is already a string, so you don’t need more quotes.