PHP stream_context_create()作用和用法

作用：创建并返回一个文本数据流并应用各种选项，可用于fopen(),file_get_contents()等过程的超时设置、代理服务器、请求方式、头信息设置的特殊过程。

函数原型：resource stream_context_create ([ array $options [, array $params ]] )

用法

例子一：

<?php
$opts = array(   'http-->array(
'method'=&gt;"GET",
'header'=&gt;"Accept-language: en\r\n" .
"Cookie: foo=bar\r\n"
)
);
 
$context = stream_context_create($opts);
 
/* Sends an http request to www.heliximitate.cn
with additional headers shown above */
$fp = fopen('http://www.heliximitate.cn', 'r', false, $context);
fpassthru($fp);
fclose($fp);
?>

例子二：

<?php
  $opts = array(    'http-->array(
'method'=&gt;"GET",
'header'=&gt;"Accept-language: en\r\n" .
"Cookie: foo=bar\r\n"
)
); 
 
$context = stream_context_create($opts);
?>

You would setup the header this way:

<?php
$opts = array(    'http-->array(
'method'=&gt;"GET",
'header'=&gt;array("Accept-language: en",
"Cookie: foo=bar",
"Custom-Header: value")
)
);
 
$context = stream_context_create($opts);
?>

例子三：

<?php
$opts = array('http' => array('proxy' => 'tcp://127.0.0.1:8080', 'request_fulluri' => true));
$context = stream_context_create($opts);
 
$data = file_get_contents('http://www.heliximitate.cn', false, $context);
 
echo $data;
 
?>

例子四：

<?php
function do_post_request($url, $postdata, $files = null)
{
    $data = "";
    $boundary = "---------------------".substr(md5(rand(0,32000)), 0, 10); 
 
    //Collect Postdata
    foreach($postdata as $key => $val)
    {
        $data .= "--$boundary\n";
        $data .= "Content-Disposition: form-data; name=\"".$key."\"\n\n".$val."\n";
    } 
 
    $data .= "--$boundary\n"; 
 
    //Collect Filedata
    foreach($files as $key => $file)
    {
        $fileContents = file_get_contents($file['tmp_name']); 
 
        $data .= "Content-Disposition: form-data; name=\"{$key}\"; filename=\"{$file['name']}\"\n";
        $data .= "Content-Type: image/jpeg\n";
        $data .= "Content-Transfer-Encoding: binary\n\n";
        $data .= $fileContents."\n";
        $data .= "--$boundary--\n";
    } 
 
    $params = array('http' => array(
           'method' => 'POST',
           'header' => 'Content-Type: multipart/form-data; boundary='.$boundary,
           'content' => $data
        )); 
 
   $ctx = stream_context_create($params);
   $fp = fopen($url, 'rb', false, $ctx); 
 
   if (!$fp) {
      throw new Exception("Problem with $url, $php_errormsg");
   } 
 
   $response = @stream_get_contents($fp);
   if ($response === false) {
      throw new Exception("Problem reading data from $url, $php_errormsg");
   }
   return $response;
} 
 
//set data (in this example from post) 
 
//sample data
$postdata = array(
    'name' => $_POST['name'],
    'age' => $_POST['age'],
    'sex' => $_POST['sex']
); 
 
//sample image
$files['image'] = $_FILES['image']; 
 
do_post_request("http://www.heliximitate.cn", $postdata, $files);
?>