Number Example – Data Type – JavaScript Syntax – JS Number Example

String Example – Data Type – JavaScript Syntax – JS String Example

Purpose: – Illustrates the for the .
Prerequistes:

Syntax: var num=new Number(123.5); num.property or num.method(); – Demonstrates how to use properties and methods of Number object.

Restrictions: None

Notes:

  • You can build your own library of syntax examples by using same web site over and over and just add new files to it.

Instructions:

  1. Use Visual Web Developer 2008
  2. Create new web site;
    • Click File/New Web Site
    • Select ASP.NET Website Template
    • Select C-Sharp for Language
    • name of Web Site could be JavaScript_Syntax.
  3. Add New folder named “DataType”
    • Right-click project name in solution explorer;
    • add new folder;
    • name of folder should be: DataType
  4. Add HTML Page Named Number to DataType folder
    • Right-click DataType folder;
    • add new item;
    • Select HTML Page
    • HTML Page name should be Number
  5. Click on copy code in code below to copy code into HTML Page Number.htm
  6. Right-click on HTML page Number and select view in browser
  7. View Example In Browser

    < !DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
     
    <html>
      <head>
        <title>Boolean</title>
        <script type="text/javascript" >
            //*****************************************************
            // Number Object
            //*****************************************************
     
            // NOTE: Number Objects are created by "new Number(value)
            //*****************************************************
     
            // GENERAL SYNTAX:
            // Properties:
            //   var num=new Number(123.5); num.property;
            // Method:
            //    var num=new Number(123.5); num.method;
     
            //*****************************************************
            //    ***    Number Object Properties   ***
            //*****************************************************
                    document.write("***NUMBER PROPERTIES***");
                    document.write("<br />");
            //    Property 	            Description
            //    constructor 	        Returns the function that created the Number object's prototype
                    var num=new Number(123.5);
                    document.write("num.constructor: " + num.constructor); // output: function Number() { [native code] }
                    document.write("<br />");
     
            //    MAX_VALUE 	        Returns the largest number possible in JavaScript
                    document.write("Number.MAX_VALUE: " + Number.MAX_VALUE); // output: 1.7976931348623157e+308
                    document.write("<br />");
     
            //    MIN_VALUE 	        Returns the smallest number possible in JavaScript
                    document.write("Number.MIN_VALUE: " + Number.MIN_VALUE); // output: 5e-324
                    document.write("<br />");
     
            //    NEGATIVE_INFINITY 	Represents negative infinity (returned on overflow)
                    document.write("Number.NEGATIVE_INFINITY: " + Number.NEGATIVE_INFINITY); // output: -Infinity
                    document.write("<br />");
     
            //    POSITIVE_INFINITY 	Represents infinity (returned on overflow)
                    document.write("Number.POSITIVE_INFINITY: " + Number.POSITIVE_INFINITY); // output: Infinity
                    document.write("<br />");
     
            //    prototype 	        Allows you to add properties and methods to an object
                    function car(make, model, year) {
                        this.make = make;
                        this.model = model;
                        this.year = year;
                    }
     
                    var myCar = new car("Toyota", "Corolla", 2002);
                    car.prototype.cost = null;
                    myCar.cost = 20000;
     
                    document.write("myCar.cost: " + myCar.cost);
                    document.write("<br />");
     
            //*****************************************************
            //    ***    Number Object Methods   ***
            //*****************************************************
                    document.write("***NUMBER METHODS***");
                    document.write("<br />");
     
            //    Method 	        Description
            //    toExponential(x) 	Converts a number into an exponential notation - x is
            //                      optional parameter that indicates precision
                    var numy = new Number(17.12344);
                    document.write("numy.toExponential(): " + numy.toExponential() + "<br />");
                    document.write("numy.toExponential(2): " + numy.toExponential(2) + "<br />");
                    document.write("numy.toExponential(4): " + numy.toExponential(4) + "<br />");
                    document.write("numy.toExponential(6): " + numy.toExponential(6));
     
            //    toFixed(x) 	    Formats a number with x numbers of digits after the decimal point
                    var numx = new Number(17.12344);
                    document.write("numx.toFixed(2): " + numx.toFixed(2) + "<br />");
     
            //    toPrecision(x) 	Formats a number to x length
                    var numz = new Number(17.12344);
                    document.write("numz.toPrecision(2): " + numz.toPrecision(2) + "<br />");
     
            //    toString() 	    Converts a Number object to a string
                    var numa = new Number(17.12344);
                    document.write("numa.toString(): " + numa.toString() + "<br />");
     
            //    valueOf() 	    Returns the primitive value of a Number object
                    var numb = new Number(17.12344);
                    document.write("numb.valueOf(): " + numb.valueOf() + "<br />");
     
     
     
     
     
        </script>
      </head>
      <body>
      </body>
    </html>