javascript check variable type code example

Example 1: javascript how to know type of variable

var foo = "Hello";
console.log(typeof foo); // string

Example 2: get type of var js

function doSomething(x) {
  if(typeof(x) === 'string') {
    alert('x is a string')
  } else if(typeof(x) === 'number') {
    alert('x is a number')
  }
}

Example 3: javascript find type of variable

> typeof "foo"
"string"
> typeof true
"boolean"
> typeof 42
"number"

if(typeof bar === 'number') {
   //whatever
}

Example 4: check type javascript

console.log(typeof "how are you?")
"string"
console.log(typeof false) / console.log(typeof true)
"boolean"
console.log(typeof 100)
"number"

Example 5: node js check type of variable

if (typeof i != "number") {
    console.log('This is not number');
}

Example 6: check data type in javascript

typeof("string"); //string
typeof(123); //number