Question

Does Javascript or jQuery have sometime like the “in” statement in Python?

“a” in “dea” -> True

Googling for the word in is hopeless 🙁

Answer 1

It does have an in operator but is restricted to object keys only:

var object = {
    a: "foo",
    b: "bar"
};

// print ab
for (var key in object) {
    print(key);
}

And you may also use it for checks like this one:

if ("a" in object) {
    print("Object has a property named a");
}

For string checking though you need to use the indexOf() method:

if ("abc".indexOf("a") > -1) {
    print("Exists");
}