Question

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 }

Answer 1

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

Answer 2

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) ) { ... }

Answer 3

if (A || B) { do something }

Answer 4

Use the || operator.

Answer 5

|| is the or operator.

if(A || B){ do something }

Answer 6

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

Answer 7

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");

Answer 8

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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