Chinese Web Sites Using PHP - v2.23, by Herong Yang
Processing Web Form Input in Latin1
This section describes how to display a Web form and process form input data in Latin1. header() function must be called to override the HTTP response header 'Content-type' setting to Latin1 in PHP 7.
Our PHP script, Web-Form-Input-Latin1.php, is not 100% working as shown in the previous tutorial. It is able to collect input. But it collects it in UTF-8 encoding, not in Latin1 encoding as I want it.
First, I reviewed the default Latin1 text in the script again. It was entered correctly.
Then I ran the script with PHP-CGI to the HTML document is generates:
C:\herong> \local\php\php-cgi Web-Form-Input-Latin1.php X-Powered-By: PHP/7.3.0 Content-type: text/html; charset=UTF-8 <html><body> <form><input type="Text" size="40" maxlength="64" name="Input" value="Télévision"/><br/> <input type="Submit" name="Submit" value="Submit"/> </form> </body></html>
I think I know the root cause of the issue. PHP-CGI.exe in PHP 7 engine automatically added "charset=UTF-8" in the Content-Type HTTP response header line.
Content-type: text/html; charset=UTF-8
This will cause the Web browser to display text and collect form input in UTF-8 encoding. And the input data will be delivered back the Web server and the PHP script in UTF-8. This is why my script receives the text in UTF-8.
I had no problem with PHP 5, because it did not specify any encoding in the HTTP response header:
C:\herong> \local\php-5\php-cgi String-GB18030.php Content-type: text/html X-Powered-By: PHP/5.0.4 <html><body> <form><input type="Text" size="40" maxlength="64" name="Input" value="Télévision"/><br/> <input type="Submit" name="Submit" value="Submit"/> </form> </body></html>
In order to fix the issue, we need to call the header() function to override the default header line very early in the PHP script before outputting text in the HTML document:
<?php
#- Web-Form-Input-Latin1-Fixed.php
#- Copyright (c) 2005 HerongYang.com. All Rights Reserved.
#
header('Content-Type: text/html; charset=Latin1');
print('<html><head>');
print('<meta http-equiv="Content-Type"'.
' content="text/html; charset=Latin1"/>');
print('</head><body>'."\n");
# Default input text
$input =
'Télévision';
$input_hex = '54E96CE9766973696F6E';
# 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 ($reply) {
print('<pre>'."\n");
print('You have submitted:'."\n");
print(' Text = '.$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-Latin1-Fixed.php. I saw a Web page with a form that has the suggested input text and a submit button.
The suggested Latin1 input characters was displayed correctly, even it was generated by my script as HTML entities.
After clicking the submit button, I saw a returning Web page with the same form and a reply section, which confirmed that the input text were correctly received in Latin1 encoding by the PHP script.
It is interesting to note that the return Web page has a special URL which contains the input text inside the query string. All characters in the input text are ASCII characters except two, which are true Latin1 characters presented as Hex values in the URL.
http://localhost/Web-Form-Input-Latin1.php ?Input=T%E9l%E9vision&Submit=Submit
Table of Contents
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
Processing Web Form Input in ASCII
Processing Web Form Input in Latin1 Encoding Error
►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