types of data js code example
Example 1: data types in javascript
//String Data Type
var strSingle = 'John'; //String with single quotes
var strDouble = "Bob"; //String with double quotes
//Number Data Type
var num = 25; //Integer
var flo = 80.5; //Floating-point number
var exp = 4.25e+6; //Exponential notation, this equates to 4250000
//Boolean Data Type
var isReading = true; //Yes, I'm reading
var isSleeping = false; //No, I'm not sleeping
//Undefined Data Type
var undef; //If a value is never assigned, any output will be 'undefined'
//Null Data Type
var noValue = null; //Null meaning that it is has no value, not the same as 0 or ""
//Object Data Type
var emptyObject = {};
var person = {"name": "Clark", "surname": "Kent", "age": "36"}; //The quotes around the propety name can be omitted if the property name is a valid JS name
var car = { //Same as person but easier to read
model: "BMW X3", //Example with quotes around property name ommitted
color: "white",
doors: 5
}
//Array Data Type
var emptyArray = []; //An array can be of any data types (string, number, boolean, etc.)
var array = ["One", "Two"] //String array, note the index of the first element is 0
//Function Data Type
var func = function() { //Calling the function: func();
alert("Code excuted"); //Outputs: Code executed
}
var funcVar = function(amount) { //Calling the function: funcVar(6);
alert("Code excuted " + amount + " times"); //Outputs: Code executed 6 times (if input was 6)
}
//Typeof Operator
typeof variable; //Returns the data type of the variable
Example 2: javascript datatypes
dataTypes = {
Numbers = 1,2,3, 100, 3.14
Strings = 'Hello, World' "helloworld@gmail.com
Boolean = true / false
Null = 'Explicitly set a variable with no Value'
Undefined = 'For variable that have not yet been defined'
Object = 'Complex data structures - Arrays, Dates, Literals etc'
Symbol = 'Used with objects' // usually not needed
}