PHP www'php'net

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PHPwww.php.net
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PHPForms

• When you use the ltformgt tag in HTML you are
  creating a form.
• A ltformgt has several uses
• A container for control elements.
• Elements are used for gathering input from users.
• Submitting user data to a web server.

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PHPForms

• Typical forms that you submit to a server-side
  script include
• order forms
• surveys
• applications
• registration forms
• search criteria

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PHPForms

• Form attributes
• Name
• Action
• Method
• Target
• id
• ltform nameorder actionprocessorder.php
  methodget(default) or post
• lt/formgt

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PHPForms

• Form attributes
• name Names the form so that it can be accessed
  by client-side scripting languages.

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PHPForms

• Form attributes
• action File name or URL of the script that will
  handle the form data.
• The PHP page that is sent the form data by the
  PHP HTTPResponse object.
• actionprocessorder.php
• This page is called to be opened and will have
  access to the submitted form data.

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PHPForms

• Form attributes
• The URL can be an absolute reference or a
  relative reference to the page.
• Relative reference
• actionprocessorder.php
• Absolute reference
• actionhttp//www.myWeb.processorder.php

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PHPForms

• Form attributes
• Method Indicates how to send the form data back
  to the web server action URL.
• value get or post
• methodget(default) or post

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PHPForms

• method"post" This method sends the form
  contents in the body of the request. Note Most
  browsers are unable to bookmark post requests.
• post method sends form data as a transmission
  separate from the URL specified by the action
  attribute.

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PHPForms

• Default is get. method"get" This method sends
  the form contents in the URL URL?namevaluename
  value.
• Note If the form values contains non-ASCII
  characters or exceeds 100 characters you MUST use
  method"post".

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PHPForm Submission

• The get method uses what is called a query
  string.
• A query string is a set of NameValue pairs
  which is appended to the target URL.
• This is based on the name of the form element.
• And the value contained in the form element.

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PHPForm Submission

• A question mark ? is used to concatenate the
  namevalue string to the URL.
• The name value pairs are separated by an
  ampersand .

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PHPForm Submission

• ltform methodget actionprocessorder.phpgt
• ltinput typetext namebook valuephp5programm
  ing /gt
• ltinput typetext nameauthor valueharris
  /gt
• lt/formgt
• What is sent is
• processorder.php?bookphp5programmingauthorharri
  s

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PHPForm Submission

• ltform methodget actionprocessorder.phpgt
• ltinput typetext namebook valuephp5programm
  ing /gt
• ltinput typetext nameauthor valueharris
  /gt
• lt/formgt
• What is sent is
• processorder.php?bookphp5programmingauthorharri
  s

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PHPHandling Form Submissions
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PHPHandling Form Submissions

• PHP includes various predefined global arrays,
• called autoglobals or superglobals, which contain
  client, server, and environment information that
  you can access in your scripts.
• Autoglobals are associative arrays like in
  JavaScript, they use alphanumeric keys instead of
  index numbers.

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PHPHandling Form Submissions

• PHP autoglobals
• are visible everywhere within a script.
• _GET
• An array of values from a form submitted with the
  GET method.
• _POST
• An array of values from a form submitted with the
  POST method.
• _REQUEST
• An array of ALL elements found in the _GET and
  _POST array.

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PHPHandling Form Submissions

• When you click a forms Submit button, each field
  on the form is submitted to the server as a
  namevalue pair.
• When the get method is specified, the name
  portion of the namevalue pair becomes the key of
  an element in the _GET autoglobal array and the
  value portion is assigned as the value of the
  element.

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PHPHandling Form Submissions

• Similarly, when the post method is specified,
  the namevalue pair become elements and values in
  the _POST autoglobal array.

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PHPHandling Form Submissions

• FYI
• Within PHP version 4.2.0 the register_globals
  directive was turned on by default.
• It is now turned OFF by default.
• This feature would allow you to just reference
  the variable value by name.
• ie name without using the _GET or _POST.
• This can cause some major security issues with
  your pages.

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PHPHandling Form Submissions

• The recommended way to retrieve data from the
  autoglobal is to use the following syntax
• _GETbook or _POSTbook
• _GETauthor or _POSTauthor

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PHPHandling Form Submissions

• Also if you dont want to depend on how a page is
  sent use the following _REQUEST autoglobal
  array.
• The recommended way to retrieve data from the
  autoglobal is to use the following syntax
• _REQUESTbook or
• _REQUESTauthor

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PHPHandling Form Submissions

• Lets look at examples to see how it all works.
• Remember this must be done on a PHP enabled
  server.