[javascript] How to use OR condition in a JavaScript IF statement?

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 }

Use the || operator.

One can use regular expressions, too:

var thingToTest = "B";_x000D_
if (/A|B/.test(thingToTest)) alert("Do something!")

Here's an example of regular expressions in general:

var myString = "This is my search subject"_x000D_
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"_x000D_
if (/my/ig.test(myString)) alert("Do something here");

|| 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

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) ) { ... }

More then one condition statement is needed to use OR(||) operator in if conditions and notation is ||.

if(condition || condition){ 
   some stuff
}

Just use ||

if (A || B) { your action here }

Note: with string and number. It's more complicated.

Check this for deep understading:

if (A || B) { do something }

You can use Like

if(condition1 || condition2 || condition3 || ..........)
{       
     enter code here
}

If we're going to mention regular expressions, we might as well mention the switch statement.

var expr = 'Papayas';_x000D_
switch (expr) {_x000D_
  case 'Oranges':_x000D_
    console.log('Oranges are $0.59 a pound.');_x000D_
    break;_x000D_
  case 'Mangoes':_x000D_
  case 'Papayas': // Mangoes or papayas_x000D_
    console.log('Mangoes and papayas are $2.79 a pound.');_x000D_
    // expected output: "Mangoes and papayas are $2.79 a pound."_x000D_
    break;_x000D_
  default:_x000D_
    console.log('Sorry, we are out of ' + expr + '.');_x000D_
}