Javascript Tips - 2

To trim a word using Javascript, use the following:
var field1 = document.formname.textbox.value.replace(/^\s+\s+$/g, "");

Deployment in JBoss

Following are the steps to deploy a war file in JBoss.
1) First, create a HTML page - form.html or a JSP file.
2) Have a folder say, CoffeeV1. Have a folder inside CoffeeV1 with the name WEB-INF. Place the form.html file or JSP inside CoffeeV1.
3) Create a folder under WEB-INF called classes.
4) Create deployment descriptor(web.xml) file with the following contents:
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE web-app PUBLIC "-//Sun Microsystems, Inc.//DTD Web Application 2.2//EN" "http://java.sun.com/j2ee/dtds/web-app_2_2.dtd"&gt;
<web-app>
<display-name>Hello Coffee</display-name>
</web-app>
5) Place the web.xml file inside WEB-INF.
6) Run the following commands to create a war file.
D:\HFSApps>cd CoffeeV1
D:\HFSApps\CoffeeV1>set CLASSPATH=C:\j2sdk1.4.2_02\bin
D:\HFSApps\CoffeeV1>set JAVA_HOME=C:\j2sdk1.4.2_02
D:\HFSApps\CoffeeV1>"%JAVA_HOME%\bin\jar.exe" -cvf CoffeeV1.war *.html WEB-INF
D:\HFSApps\CoffeeV1>copy CoffeeV1.war C:\jboss\server\default\deploy\
7) Start the JBoss server using run.bat command.
8) In web browser, enter http://localhost:8080/CoffeeV1/form.html.

Javascript Tips

1) Hide a form element using javascript:
The following is a simple textbox which will be hidden by default:
<input type="text" id="text_id" name="text_name" style="visibility: hidden">
The following javascript code will make the hidden textbox visbile.
document.getElementById('text_id').style.visibility = 'visible';

2) Working with <SELECT> tags.
A simple <SELECT> tag would be created as follows:
<SELECT name="select_name" id="select_id"></SELECT> - This creates an empty drop down list.
<SELECT name="select_name" id="select_id"><OPTION value="1">1</OPTION></SELECT> - This creates a drop down with a value 1 and text as 1.
Adding a new option dynamically using javascript
var txt = '2'; // txt is the value that is set as the text of the option
var val = '2'; // val is the value that is set in the 'value' attribute of the option
var newOpt = new Option( txt, val, false); // Creating a new option object. false implies this option will not be pre-selected in the drop down on adding to the <SELECT> option.
document.<form_name>.<select_name>.options[document.<form_name>.<select_name>.options.length] = newOpt; // Assigns the newly created option to the <SELECT> list.
Getting the length of a drop down list.
document.<form_name>.<select_name>.options.length
Getting a pointer to the value that is pre-selected in the drop down currently.
document.<form_name>.<select_name>.selectedIndex.text - This returns the text that is set for the selected option.
document.<form_name>.<select_name>.selectedIndex.value - This returns the value that is set for the selected option.
Removing an element from the <SELECT> list
var x=document.<form_name>.<select_name>;
x.remove(x.selectedIndex);

3) Confirmation alert
var input_box=confirm("Do you want to delete the selected network set?");
if (input_box==true)
{
alert("You clicked OK");
}else{
alert("You clicked Cancel");
}