Why is null length returning 4?

General Discussions
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4

I’ve run into this during testing edge cases—especially with form inputs.

Adding on to what @kumari_babitaa and @joe-elmoufak said, the key here is understanding that "" (empty string) is still a valid value and has a .length—even if it’s zero. And because JavaScript is loose with types, it’s easy to confuse that with null.

To make your condition truly robust when checking javascript not null and ensuring it’s not an empty value either, this snippet works well:

if (val != null && val !== "") {
    alert("value is " + val.length);
} else {
    alert("value* is null or empty");
}

One small tip: if this logic shows up often in your codebase, you might consider wrapping it in a utility function to keep things DRY.