# stream_context_set_default

(PHP 5 >= 5.3.0, PHP 7)

stream_context_set_default — Set the default stream context

### 说明

stream_context_set_default ( array `$options` ) : resource

Set the default stream context which will be used whenever file operations (fopen(), file_get_contents(), etc...) are called without a context parameter. Uses the same syntax as stream_context_create().

### 参数

`options`

  The options to set for the default context.

  > Note:

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

### 返回值

Returns the default stream context.

### 范例

Example #1 stream_context_set_default() example

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

    $default = stream_context_set_default($default_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');
    ?>

### 参见

- stream_context_create() - 创建资源流上下文
- stream_context_get_default() - Retrieve the default stream context
- Listing of supported wrappers with context options (支持的协议和封装协议).