JavaScript can enhance input fields

There are a number of different ways to collect dates from your visitors. Perhaps the simplest way is to display a calendar and allow your visitors to simply click on the date they want. The selected date can then be inserted into a text field in your form for subsequent processing.

Date Selector

With JavaScript you can tell your visitors what they entered incorrectly into a form before the form is submitted.

Dates can be entered in a lot of different formats. This ready to use JavaScript can recognise many of the formats that dates can be entered in. It can also validate that the date entered is not in the future or not in the past (whichever is appropriate for your requirements). If your form requires dates be entered into text fields then you need this script.

Date Validation

JavaScript can update drop down list content

One way of getting your visitors to enter dates is via drop down lists. This script allows you to automatically set the default options selected to today's date.

Selecting Today's Date

Regular Expressions can match groups of characters.

Up until now we have looked at regular expressions involving single characters and repetitions of single characters. The fourteenth tutorial on regular expressions introduces you to a way to group characters together allowing you to test for repeating groups.

Grouping

Some ways of using JavaScript are better than others

There are four different ways that you can attach JavaScript into your web page. Not all of them are suitable to use in all situations.

JavaScript and HTML

Modern JavaScript is almost a new language

The JavaScript language today is vastly different from what it was just a few years ago. Separating our HTML, StyleSheets and JavaScript into separate files to define the content, appearance, and behaviour separately means that the way you code your scripts is now completely different. How can you learn this new approach. One book that teaches this new approach is Simply JavaScript.

JavaScript provides all the validation options you need in several different ways.

The eighth form validation tutorial looks at the reverse of what we looked at last time - how to test for when certain characters are only allowed when they are adjacent to certain other characters.

Only Adjacent

JavaScript can set up multimedia downloads

Place a background audio selector box on your web page to allow your visitors to download and play music.

Background Audio Selector

The best menus are still functional when JavaScript is disabled.

The suckerfish dropdown menu was the name given to the first dropdown menu for web pages designed using just HTML and CSS with no Javascript required (except to handle some CSS support that is missing from Internet Explorer). In my version of this menu I have also added some further Javascript that will enhance the functionality of the menu without stopping the menu from still being usable when Javascript is disabled.

Enhanced Suckerfish Menu

JavaScript can create all sorts of unusual calculators

This calculator script is rather specialized in what it does and will probably only be of interest to piano teachers (as an actual calculator). It does make use of several rather unique Javascript coding techniques such as Drawing with CSS, Passing multiple values in one form field, Multi dimensional arrays, and How to test stylesheet colours. See how I managed to combine all of these together to produce the Piano Chord Calculator.

Piano Chord Calculator