HTTP Response Header Lines

This section describes HTTP response header lines in 3 groups. Commonly used header lines are Date, Cache-Control, Last-Modified, Content-Length, Connection, Content-Type, Expires, Set-Cookie, Server, etc.

HTTP/1.1 response header lines allow the server to passes additional information about the response which cannot be placed in the status line. Header lines can be divided into three groups:

1. General header lines - Information about the transmission of the entire response message:

   Cache-Control      
   Connection         
   Date               
   Pragma             
   Trailer            
   Transfer-Encoding  
   Upgrade            
   Via                
   Warning          

2. Response header lines - Information about the response:

   Accept-Ranges     
   Age               
   ETag              
   Location          
   Proxy-Authenticate
   Retry-After       
   Server            
   Vary              
   WWW-Authenticate

3. Entity header lines - Information about the data requested by the client:

   Allow              
   Content-Encoding   
   Content-Language   
   Content-Length     
   Content-Location   
   Content-MD5        
   Content-Range      
   Content-Type       
   Expires            
   Last-Modified      

As examples, here is a list of all header lines from an HTTP response returned from the Yahoo Web serer:

Date: Sun, 13 Nov 2005 04:34:17 GMT
P3P: policyref="http://info.yahoo.com/w3c/p3p.xml", CP="CAO DSP CO...
Cache-Control: private
Vary: User-Agent
X-XRDS-Location: http://open.login.yahooapis.com/openid20/www.yaho...
Last-Modified: Sun, 13 Nov 2005 04:31:16 GMT
Accept-Ranges: bytes
Content-Length: 9490
Connection: close
Content-Type: text/html; charset=utf-8

Last update: 2015.

Table of Contents

 About This Book

 Introduction and Installation of PHP 7.0

 PHP Script File Syntax

 PHP Data Types and Data Literals

 Variables, References, and Constants

 Expressions, Operations and Type Conversions

 Conditional Statements - "if" and "switch"

 Loop Statements - "while", "for", and "do ... while"

 Function Declaration, Arguments, and Return Values

 Arrays - Ordered Maps

 Configuring and Sending out Emails

 Retrieving Information from HTTP Requests

 Creating and Managing Sessions in PHP Scripts

 Sending and Receiving Cookies in PHP Scripts

Controlling HTTP Response Header Lines in PHP Scripts

 What Is an HTTP Response?

HTTP Response Header Lines

 header() - Inserting a Raw Header Lines

 HttpRequestGet.php - Viewing Header Lines

 Response Header Lines of Static Files

 HttpHeaderLines.php - Examples of Inserting Header Lines

 Location: - Forcing the Browser to Redirect to Another URL

 Content-Type: - Generating Non-HTML Response Body

 Content-Disposition: - Sending Files for Downloading

 MySQL Server Connection and Access Functions

 Functions to Manage Directories, Files and Images

 SOAP Extension Function and Calling Web Services

 SOAP Server Functions and Examples

 Localization Overview of Web Applications

 Using Non-ASCII Characters in HTML Documents

 Using Non-ASCII Characters as PHP Script String Literals

 Receiving Non-ASCII Characters from Input Forms

 "mbstring" Extension and Non-ASCII Encoding Management

 Managing Non-ASCII Character Strings with MySQL Servers

 Introduction of Class and Object

 Integrating PHP with Apache Web Server

 Outdated Tutorials

 References

 PDF Printing Version