errror checking if a user input is a number javascript code example

Example 1: javascript check if a value is a integer number

Number.isInteger(123) //true
Number.isInteger(-123) //true
Number.isInteger(5-2) //true
Number.isInteger(0) //true
Number.isInteger(0.5) //false
Number.isInteger('123') //false
Number.isInteger(false) //false
Number.isInteger(Infinity) //false
Number.isInteger(-Infinity) //false
Number.isInteger(0 / 0) //false

Example 2: check to see if number is a decimal javascript

The Number. isInteger() method determines whether a 
value an integer. 
This method returns true if the value is of the type 
Number, and an integer (a number without decimals). 
Otherwise it returns false.