js how to check type code example

Example 1: 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 2: js typeof number

console.log(typeof 93);
// Output = "number"

console.log(typeof 'Maximum');
// Output = 'string'

console.log(typeof false);
// Output = "boolean"

console.log(typeof anUndeclaredVariable);
// Output = "undefined"

Example 3: 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 4: javascript check type of variable var

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