(PHP 5 >= 5.1.0)
stream_context_get_default — Retreive the default streams context
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).