|| (or) in the if statement in JavaScript isn't working

Question

When I use the or in the if statement, it pretends like there is no ||.

Example:

if (code !== "" || null) {
    document.getElementById("person_name").innerHTML = "Welcome " + name + "!";
} else {
    document.getElementById("person_name").innerHTML = "I'm sorry, but you didn't enter your name.";
}

I am using the window.prompt in JavaScript to alert anyone to put their first name in the box and it should output it. If someone just presses enter without putting anything in the box, it should say, "I am sorry, but you didn't enter your name." If someone exits out of the prompt box, it should say the same thing.

Could you provide an example: expected output versus actual output? — Jeremy, May 06 '17 at 22:21
`||` is an operator. Here, its two operands are `code !== ""` and `null`. Doesn’t work like English. — Ry-, May 06 '17 at 22:22

Hubert Grzeskowiak · Accepted Answer · 2017-05-06T22:32:13.273

1

The != operator has higher precedence than || so your statement reads as "if (code is not equal to empty string) OR null" and null always evaluates to false.

What you rather want is:

if (code !== "" && code !== null) {...

edited May 06 '17 at 22:32

answered May 06 '17 at 22:22

Hubert Grzeskowiak

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|| (or) in the if statement in JavaScript isn't working

1 Answers1