JavaScript

Javascript gives you the ability to open new windows in you’re browser. You’ll also have the ability to run any code in these windows, you could even have actions in the one window that will affect another window. The following statement is used to open up a basic popup window window.open(“popup.html”,”PopUp...

window.location.href = 'redirect.html';

By using the isNaN() JavaScript function. isNaN = Is Not A Number
Examples:
document.write(isNaN(“Hello World!”)); //Will print true since Hello World! is not a number
document.write(isNaN(123456)); //Will print false, since 123456 is a number.
var phoneNumber = 0724956785234;
if(isNaN(phoneNumber) == true){
alert(“Please enter a valid phone number”);
return false;
}

There are two JavaScript function that you can use to accomplish this

 encodeURIComponent()

Encodes a URI component
Encodes special characters
The following characters: , / ? : @ & = + $ # are encoded

var url=""+encodeURIComponent(url);

encodeURI()

Encode a URI
Encodes special characters but not (except) , / ? : @ & = + $ #

var url=""+encodeURI(url);

var iframe = document.getElementById('iframe_id');
iframe.src = iframe.src;

iframe_id is the ID of the IFrame

document.getElementById('iframe_id').src = 'newpage.html

iframe_id = The ID for the IFrame
newpage.html = The page that you want to load into the IFrame

If we want to call a function every 10 seconds using JavaScript we can accomplish it by implementing the following piece of code window.setInterval('yourfunction()', 1000);   function yourfunction(){ alert('test');   } With the code above every 10 seconds a JavaScript function with the name yourfunction will be called that will prompt an alert. window.setInterval = Evaluates an expression each...

To enable a form field use the below JavaScript

document.getElementById("ELEMENT_ID").disabled = false;

And to disable the form field use the below JavaScript

document.getElementById("ELEMENT_ID").disabled = true;

NOTE: Replace ELEMENT_ID with the form fields ID

var filename = 'myFile.jpg';
var ext = filename.split('.').pop();  //We split the filename on every instance where the . is found and then getting the last element in the array using the pop() function
alert(ext);

Add the following JavaScript function to your HTML page   function isNumberKey(evt) {      var charCode = (evt.which) ? evt.which : event.keyCode      if (charCode > 31 && (charCode < 48 || charCode > 57))         return false;        return true; } The above function checks the input of the user and then returns false if no number has been entered and true if a number has been...

Use the string.toLowerCase() function as the example below

 
<script type="text/javascript">
 
var str="I NEED THIS STRING TO BE CONVERTED TO LOWER CASE";
 
document.write(str.toLowerCase());
 
</script>

Use the history.go(-1) function in conjunction with the anchor html element
Example

<a href="javascript: history.go(-1);">Go back to previous page</a>

If you have a text input box with ID age and you want to obtain the value for the text box via JavaScript use the JavaScript function getElementById() to get the value
Html input text box

<input type="text" name="age" id="age" value="12" />

JavaScript function

<script type="text/javascript">
 
var age = document.getElementById('age').value;
 
</script>

If you have a JSON encoded string that you might have received from a ajax scriptand you need to decode it using JavaScript you can use the eval() function to decode the string. The eval() function evaluates or executes an given argument.
Example:

var string = '{"id" : 32}';
var d = eval('(' + string + ')');
alert(d.id); //will alert 32

This can be obtained by using the Pre-defined object (Date) in JavaScript
Example:

document.write("The current date is:"+Date())

To get the total size of the array elements within an JavaScript array the JavaScriptlength property can be used.
E.g.

var arr = new Array();
 
arr[0] = 'val 1';
 
arr[1] = 'val 2';
 
 
 
alert(arr.length); //Will output 2

Create a JavaScript function called suppressJS()

function suppressJS(){return true;}

Then within the head tags add the following code

window.onerror=suppressJS;

Your complete code will look like this

<script type="text/javascript">
 
<!--
 
function suppressJS(){return true;}
 
window.onerror=suppressJS;
 
//-->
 
</script>

Use the following code to obtain the full URL

[code]var fullURL = window.location.href;
alert(fullURL);[/code]

location.href holds the current URL for reference purposes and can be changed at any time. Once changed the page will reload with the new assigned URL