How can I check for an empty/undefined/null string in JavaScript?

javascript null is-empty
casademora picture casademora · Sep 30, 2008 · Viewed 3.4M times · Source

I saw this question, but I didn't see a JavaScript specific example. Is there a simple string.Empty available in JavaScript, or is it just a case of checking for ""?

Answer

bdukes picture bdukes · Sep 30, 2008

If you just want to check whether there's any value, you can do 

if (strValue) {
    //do something
}

If you need to check specifically for an empty string over null, I would think checking against "" is your best bet, using the === operator (so that you know that it is, in fact, a string you're comparing against).

if (strValue === "") {
    //...
}

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