Streams
PHP Manual

stream_context_get_default

(PHP 5 >= 5.1.0)

stream_context_get_default — Retreive the default streams context

Description

resource stream_context_get_default ([ array $options ] )

Returns the default stream context which is used whenever file operations (fopen(), file_get_contents(), etc...) are called without a context parameter. Options for the default context can optionally be specified with this function using the same syntax as stream_context_create().

options must be an associative array of associative arrays in the format $arr['wrapper']['option'] = $value.

Example#1 Using stream_context_get_default()

<?php
$default_opts 
= array(
  
'http'=>array(
    
'method'=>"GET",
    
'header'=>"Accept-language: en\r\n" 
              
"Cookie: foo=bar",
    
'proxy'=>"tcp://10.54.1.39:8000"
  
)
);


$alternate_opts = array(
  
'http'=>array(
    
'method'=>"POST",
    
'header'=>"Content-type: application/x-www-form-urlencoded\r\n" .
              
"Content-length: " strlen("baz=bomb"),
    
'content'=>"baz=bomb"
  
)
);

$default stream_context_get_default($default_opts);
$alternate stream_context_create($alternate_opts);

/* Sends a regular GET request to proxy server at 10.54.1.39
 * For www.example.com using context options specified in $default_opts
 */
readfile('http://www.example.com');

/* Sends a POST request directly to www.example.com
 * Using context options specified in $alternate_opts
 */
readfile('http://www.example.com'false$alternate);

?>

See also stream_context_create(), and Listing of supported wrappers with context options (支持的协议/封装协议列表).


Streams
PHP Manual