Smart way to check if every entry in a object is not null or undefined

Question

I have got an object, that may look like this:
{
  address: {
    street: undefined,
    country: 'GB'
  },
  givenname: 'Marko',
  surname: null,
}

I want to know if all fields are set or if at least one is null. Is there a smarter / shorter way to dot his in javascript than
address.street != null && address.country != null && givenname != null && surname != null

Maybe something that looks like this:
// this could return true or false?
nullCheck(address.street, address.country, givenname, surname)

Jorge Fuentes González · Answer

The first one is the typical way to go actually. Works fine specially if you have typings, like with TypeScript.
The second one is just the same but with a bit of overhead (each time you enter/exit a function, adss a bit of overhead), although is really small overhead only noticeable when you have tons of iterations. You can detect the arguments dynamically:


const nullobj = {
    value1: "yay",
    value2: "",
    value3: 23,
    value4: null
};
const obj = {
    value1: "yay",
    value2: "",
    value3: 23,
    value4: "ok"
};

function checkArgumentsNull(...args) {
    for (let v of args) {
        if (v == null) {
            return true;
        }
    }
    return false;
}

console.log("nullobj:", checkArgumentsNull(nullobj.value1, nullobj.value2, nullobj.value3, nullobj.value4));
console.log("obj:", checkArgumentsNull(obj.value1, obj.value2, obj.value3, obj.value4));

But if you are going to check dynamically for arguments, you can check dynamically for properties, which is easier. Just saw your edit and this one can be easily converted to a recursive one that will check for sub-objects. Actually all functions here can be converted to recursive ones following this principle:


const nullobj = {
    value1: {
        ok: "ok",
        notok: null
    },
    value2: "",
    value3: 23,
    value4: "ok"
};
const obj = {
    value1: {
        ok: "ok",
        notok: "no"
    },
    value2: "",
    value3: 23,
    value4: "ok"
};

function checkPropertiesNull(obj) {
    for (let v in obj) {
        if (obj[v] == null || (typeof obj[v] === "object" && checkPropertiesNull(obj[v]))) {
            return true;
        }
    }
    return false;
}

console.log("nullobj:", checkPropertiesNull(nullobj));
console.log("obj:", checkPropertiesNull(obj));

And for the sake of modern JavaScript, you can even pass an iterator, and you can check whatever iterable object you can imagine of (object, arrays, maps, sets, etc):


const nullobj = {
    value1: "yay",
    value2: "",
    value3: 23,
    value4: null
};
const obj = {
    value1: "yay",
    value2: "",
    value3: 23,
    value4: "ok"
};
const nullarr = ["ok", "yay", null];
const arr = ["ok", "yay", "yay2"];

function checkIteratorNull(it) {
    for (let v of it) {
        if (v == null) {
            return true;
        }
    }
    return false;
}

console.log("nullobj:", checkIteratorNull(Object.values(nullobj)));
console.log("obj:", checkIteratorNull(Object.values(obj)));
console.log("nullarr:", checkIteratorNull(nullarr));
console.log("arr:", checkIteratorNull(arr));

Mati Tucci · Answer

You can use .some


const hasAnEmptyValue = (obj) => Object.values(obj).some(value => !value)

const obj1 = {
  address: null,
  givenname: 'Rick',
  surname: 'Sanchez',
}

const obj2 = {
  address: 'Argentina',
  givenname: 'Rick',
  surname: 'Sanchez',
}
    
console.log(hasAnEmptyValue(obj1))

console.log(hasAnEmptyValue(obj2))

Luke Storry · Answer

You can use the every method, given a list of variables to check, with a callback that checks for null.


let address = {
    street: undefined,
    country: 'GB'
  },
  givenname = 'Marko',
  surname = null;

console.log([address.street, address.country, givenname, surname].every(e => e !== null))

surname = "blah"

console.log([address.street, address.country, givenname, surname].every(e => e !== null))

Alejov · Answer

Yes, there is.
You can use the Object data type, and the includes array method like this:
Object.values(your_object).includes(null)

This will return true if your object contains at least one null element and false if it doesn't contain any.
This answer only works for 1 level deep objects.
Object Documentation
Array.includes Documentation

Smart way to check if every entry in a object is not null or undefined

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