Processing Web Form Input in UTF-8

This section describes how to display a Web form and process form input data in UTF-8.

The next test I did was to try to enter UTF-8 characters as Web form input. I wrote a new test PHP script with some interesting features:

<?php 
#- Web-Form-Input-UTF8.php
#- Copyright (c) 2015, HerongYang.com, All Rights Reserved.
#
  print('<html><head>');
  print('<meta http-equiv="Content-Type"'.
    ' content="text/html; charset=utf-8"/>');
  print('</head><body>'."\n");

# Default input text
  $input =
    '&#x54;&#xC3;&#xA9;&#x6C;&#xC3;&#xA9;&#x76;&#x69;&#x73;'
    .'&#x69;&#x6F;&#x6E';
  $input_hex = '54C3A96CC3A9766973696F6E'; 

# Form reply determination
  $reply = isset($_REQUEST["Submit"]);

# Process form input data
  if ($reply) {
    if (isset($_REQUEST["Input"])) {
      $input = $_REQUEST["Input"];
    }
  }

# Display form
  print('<form>');
  print('<input type="Text" size="40" maxlength="64"'
   . ' name="Input" value="'.$input.'"/><br/>');
  print('<input type="Submit" name="Submit" value="Submit"/>');
  print('</form>'."\n");

# Display reply
  if ($reply) {
    print('<pre>'."\n");
    print('Content-Type:'."\n");
    print('  text/html; charset=utf-8'."\n");
    print('You have submitted:'."\n");
    print('  Text = '.$input."\n");
    print('  Text in HEX = '.strtoupper(bin2hex($input))."\n");
    print('  Default HEX = '.$input_hex."\n");
    print('</pre>'."\n");
  } 

  print('</body></html>');
?>

After moving this PHP script file to Apache server document directory, I tested it with Internet Explorer (IE) with this URL: http://localhost/Web-Form-Input-UTF8.php. I saw a Web page with a form that has the suggested input text and a submit button.

However, the French characters in the default text encoded in UTF-8 were not displayed correctly.

After clicking the submit button, I saw a returning Web page with the same form and a reply section. Since the default text was not displayed correctly, the PHP received incorrect UTF-8 byte sequences:
Processing Web Form Input in UTF-8

It is interesting to note that the return Web page has a special URL which contains the input text inside the query string. The special characters are included as Hex values of UTF-8 byte sequences:

http://localhost/Web-Form-Input-UTF8.php
  ?Input=T%C3%83%C2%A9l%C3%83%C2%A9vision&Submit=Submit

Conclusion: IE can not take UTF-8 byte sequences as Hex values in the format like &#xC3A9.

Last update: 2015.

Table of Contents

 About This Book

 PHP Installation on Windows Systems

 Integrating PHP with Apache Web Server

 charset="*" - Encodings on Chinese Web Pages

 Chinese Characters in PHP String Literals

 Multibyte String Functions in UTF-8 Encoding

Input Text Data from Web Forms

 Steps and Components Involved

 Processing Web Form Input in ASCII

 Processing Web Form Input in Latin1

 Entering Latin1 Characters with Alt Keycodes

 Testing Latin1 Alt Keycodes with IE

Processing Web Form Input in UTF-8

 Outputting Form Default Input Text in UTF-8

 Testing Alt Keycodes with IE on a UTF-8 Web Page

 Input Chinese Text Data from Web Forms

 MySQL - Installation on Windows

 MySQL - Connecting PHP to Database

 MySQL - Character Set and Encoding

 MySQL - Sending Non-ASCII Text to MySQL

 Retrieving Chinese Text from Database to Web Pages

 Input Chinese Text Data to MySQL Database

 References

 PDF Printing Version