check typeof javascript code example

Example 1: type of variable js

// get type of variable

var number = 1
var string = 'hello world'
var dict = {a: 1, b: 2, c: 3}

console.log(typeof number) // number
console.log(typeof string) // string
console.log(typeof dict)   // object

Example 2: 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 3: type of javascript

//typeof() will return the type of value in its parameters.
//some examples of types: undefined, NaN, number, string, object, array

//example of a practical usage
if (typeof(value) !== "undefined") {//also, make sure that the type name is a string
  	//execute code
}

Example 4: check data type in javascript

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

Example 5: javascript check type of variable var

// You can use the built-in method 'typeof' in order to check the variable datatype

//examples:

typeof "hello" // "string"

//or
var a = 1;
typeof(a);
//the output will be > 'number'

Example 6: javascript typeof

exports.is = (data) => {
const isArray = Array.isArray(data) && 'array'
const isObject = data == {} && 'object'
const isNull =  data == null && 'null'

const isGrouping =  isArray || isObject || isNull
const isCheck = !isGrouping ? typeof data : isGrouping

const isTypeData = ['number','string','array','symbol','object','undefined','null','function', 'boolean']
const isMatch = isTypeData.indexOf(isCheck)
const isResult = isTypeData[isMatch]
return isResult
}