How to use OR condition in a JavaScript IF statement? - Stack Overflow

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I understand that in JavaScript you can write:

if (A && B) { do something }

But how do I implement an OR such as:

if (A OR B) { do something }

I understand that in JavaScript you can write:

if (A && B) { do something }

But how do I implement an OR such as:

if (A OR B) { do something }

• javascript
• if-statement
• boolean-expression

Share Improve this question Follow edited Jan 11, 2023 at 20:19 TylerH 21.2k7676 gold badges7979 silver badges110110 bronze badges asked Mar 2, 2010 at 14:38 sadmicrowavesadmicrowave 40.9k3434 gold badges113113 silver badges184184 bronze badges 0

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8 Answers 8

Sorted by: Reset to default 333

Use the logical "OR" operator, that is ||.

if (A || B)

Note that if you use string comparisons in the conditions, you need to perform a comparison for each condition:

if ( var1 == "A" || var1 == "B" )

If you only do it in the first one, then it will always return true:

if ( var1 == "A" || "B" ) //don't do this; it is equivalent to if ("B"), which is always true

The official ECMAScript documentation can be found here

Worth noting that || will also return true if BOTH A and B are true.

In JavaScript, if you're looking for A or B, but not both, you'll need to do something similar to:

if( (A && !B) || (B && !A) ) { ... }

if (A || B) { do something }

Use the || operator.

|| is the or operator.

if(A || B){ do something }

here is my example:

if(userAnswer==="Yes"||"yes"||"YeS"){
 console.log("Too Bad!");   
}

This says that if the answer is Yes yes or YeS than the same thing will happen

One can use regular expressions, too:

var thingToTest = "B";
if (/A|B/.test(thingToTest)) alert("Do something!")

Here's an example of regular expressions in general:

var myString = "This is my search subject"
if (/my/.test(myString)) alert("Do something here!")

This will look for "my" within the variable "myString". You can substitute a string directly in place of the "myString" variable.

As an added bonus you can add the case insensitive "i" and the global "g" to the search as well.

var myString = "This is my search subject"
if (/my/ig.test(myString)) alert("Do something here");

You may also want to filter an IF statement when condition1 equals 'something' AND condition2 equals 'another thing' OR 'something else'. You can do this by placing condition2 in another set of brackets eg...

if (condition1 === 'x' && (condition2 === 'y' || condition2 === 'z')) {
    console.log('do whatever')
}

If condition2 is NOT in it's own brackets then condition1 has to be x AND condition2 has to be y for the function to trigger...

... but it will also trigger if condition2 is z, regardless of what condition1 is. Which may be okay depending on your use case, but something to be mindful of.

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