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Unit 9: Web Techniques
value=”<?=$varMovie;?>” /> Notes
</p>
<p>
<label for=’formName’>What is your name?</label><br/>
<input type=”text” name=”formName” maxlength=”50”
value=”<?=$varName;?>” />
</p>
<p>
<label for=’formGender’>What is your Gender?</
label><br/>
<select name=”formGender”>
<option value=””>Select...</option>
<option value=”M”<? if($varGender==”M”) echo(“
selected=\”selected\””);?>>Male</option>
<option value=”F”<? if($varGender==”F”) echo(“
selected=\”selected\””);?>>Female</option>
</select>
</p>
<input type=”submit” name=”formSubmit” value=”Submit” />
</form>
<p>
<a href=’http://www.html-form-guide.com/php-form/php-form-processing.html’
>’PHP form processing’ book page</a>
</p>
</body>
</html>
9.5 Setting Response Headers
As we have already discussed, the HTTP response that a server sends back to a client contains
headers that identify the type of content in the body of the response, the server that sent the
response, how many bytes are in the body, when the response was sent, etc. PHP and Apache
normally take care of the headers for you, identifying the document as HTML, calculating
the length of the HTML page, and so on. Most web applications never need to set headers
themselves. However, if you want to send back something that’s not HTML, set the expiration
time for a page, redirect the client’s browser, or generate a specific HTTP error, you will need
to use the header( ) function.
The only catch to setting headers is that you must do so before any of the body is generated.
This means that all calls to header ( ) (or setcookie( ), if you are setting cookies) must happen
at the very top of your file, even before the <html> tag. For example:
<?php header(‘Content-Type: text/plain’); ?> Date: today From: fred To: barney Subject: hands
off! My lunchbox is mine and mine alone. Get your own, you filthy scrounger!
LOVELY PROFESSIONAL UNIVERSITY 213
