Javascript error: Function not defined

For some reason, I seem to be hitting a roadblock with this basic function. It's telling me there's a reference error because apparently "isEven" is undefined:


var isEven = function(number) {
    if (number % 2 == 0) {
        return true;
    }
    else {
        return false;
    };
};

I can't seem to figure out what I'm missing or doing incorrectly. Any insights?

Answer №1

Make sure to use an equality check instead of an assignment operation in the if clause. Adjust the second line from

number % 2 = 0

to read like this:

(number % 2) == 0

The error you're encountering is due to using the wrong syntax initially, leading to a function not being defined properly. Remember to address syntax errors before attempting to call functions.

Answer №2

Make sure to use "== or "===" in your if statement, not just "=", this will properly compare the number%2 value to zero.

var isEven = function(number) {
    if (number%2==0) {
        return true;
    }
    else {
        return false;
    };
};

Answer №3

(=) Sets Value and (==) Compares the value

function checkIfEven(inputNumber) {
    if ((inputNumber % 2) == 0) {
        return true;
    } else {
        return false;
    }
};


Step One:

(inputNumber % 2)   

Finds the remainder when divided by two

Step Two:

(inputNumber % 2) == 0

Checks if the remainder is zero.


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