check if string is integers only javascript code example

Example 1: js check if string is integer

function isInt(str) {
  return !isNaN(str) && Number.isInteger(parseFloat(str));
}

Example 2: js check if string is int

function isNumeric(str) {

	// Check if input is string
	if (typeof str != "string")
    	return false

	// Use type coercion to parse the _entirety_ of the string
    // (`parseFloat` alone does not do this).
	// Also ensure that the strings whitespaces fail
	return !isNaN(str) && 
		!isNaN(parseFloat(str)) 
}

Example 3: js check if string or int

var myString     =  "abc123";
var otherString  =  "123";
/* isInterger() checks if an value repersents an int  */

Number.isInteger(myString);    //returns false
Number.isInteger(otherString); //returns true