No, there is no built-in property that tells you how many properties the object has (which is what you’re looking for).
The closest I can think of are two ES5 and higher features, Object.keys
(spec | MDN) and Object.getOwnPropertyNames
(spec | MDN). For instance, you could use Object.keys
like this:
console.log(Object.keys(quesArr).length); // "3"
Object.keys
returns an array of the names of an object’s own enumerable string-named properties. But internally (in theory) it’s that loop you didn’t want to use (and the polyfill for it for pre-ES5 environments uses a loop, of course). If you also want non-enumerable string-named properties, you’d use Object.getOwnPropertyNames
instead.
In ES2015+, an object can have properties whose keys are Symbols rather than strings. Object.getOwnPropertySymbols
(spec | MDN) lets you get them.
FWIW, unless you’re going to use the Array
features of the object, don’t make it an array. Instead:
var quesArr = {};
quesArr["q101"] = "Your name?";
quesArr["q102"] = "Your age?";
quesArr["q103"] = "Your school?";
Those keys don’t have to be given as string literals in square brackets, either, if you don’t want them to be (whether you use an array or a plain object):
var quesArr = {};
quesArr.q101 = "Your name?";
quesArr.q102 = "Your age?";
quesArr.q103 = "Your school?";
But you can use the other notation if you prefer; they’re exactly equivalent except that with dotted notation the keys must be valid identifier names (in bracketed notation they can be anything).
You can even do this:
var quesArr = {
q101: "Your name?",
q102: "Your age?",
q103: "Your school?"
};
or (if the keys won’t be valid identifiers):
var quesArr = {
"q101": "Your name?",
"q102": "Your age?",
"q103": "Your school?"
};
Those can be single or double quotes.