Session 8: Working with Form

iNET Academy

Open Source Web Development

Objectives

Bulding a Form and Accessing Form’s Values Types of Input & Validating Data Query the DB with form data Using Template

Building a Form

Every form must have three basic components The submission type defined with the method keyword One or more input elements defined with the input tag The destination to go to when submitted defined with the action

keyword

Accessing Submitted Form Values

Using

Accessing Submitted Form Values (cont.) Use super global variables

$_GET[field] $_POST[field] $_REQUEST[field]

register_globals should be off

Default Values

Types of Input – Text boxes

Used to capture strings from the user The name attribute: used to reference to the value The size attribute: specifies the length of the text box The maxlength attribute: determines the maximum number of

characters

Types of Input – Text areas

A text area is defined using the text area element The name attribute The cols attribute: specifies how many character columns to create The rows attribute: specifies how many rows to create

Types of Input – Check boxes

Used to give users several different options Use input element with type=“checkbox” The name attribute The value attribute

Types of Input – Radio Button

Give the user several choice but can choose only one value

Types of Input - Hidden

The information of hidden fields is not visible to the users

Types of Input - Selects

Present a list of options to the user

Attributes of the <select> The name attribute The size attribute: specifies how many lines of the list appear in the

browser window The multiple attribute: allow the user to select more than one item from

the list Attributes of the <option>

The selected attribute specifies a default selection The value attribute specifies a value that is different from the label of

the option. If no value is specidied, the label is used as the value

Types of Input – Selects (cont.)

Working with Multiple Values

Working with Multiple Values (cont.)

Validating Data

Always validate data getting from users Validating checkboxes, radio buttons and selects

Validating Data (cont.)

Validating text boxes and text areas Decide which information is valid and which is not Check for empty values Check for other conditions like @ in a email field

Building a Feet-to-Meters Converter in PHP

Building a Time-Zone Conversion Utility in PHP

Building a Time-Zone Conversion Utility in PHP (cont.)

Building a Time-Zone Conversion Utility in PHP (cont.)

Query the Db with Form Data

Query the Db with Form Data (cont.)

Query the Db with Form Data (cont.)

Query the Db with Form Data (cont.)

Practice

In this practice, you will Write an program to search for a book based

on only one of three following condition Author Title Price