如何使用PHP和CURL上传多维POSTFIELDS的文件(multipart / form-d

多维数组例如：

$post['question'] = 'Are you human?';
$post['answers'] = array('yes','no','maybe');
$post['file'] = '@/path/to/file';

// Output:

Array(
    'question' => Are you human?,'answers' => Array(
        '0' => yes,'1' => no,'2' => maybe
        ),'file' => @/path/to/file
)

如果您只是尝试使用CURL中的CURLOPT_POSTFIELDS发布此内容,那么为什么这不起作用有以下几种：

$ch = curl_init();

curl_setopt($ch,CURLOPT_URL,'http://example.com');
curl_setopt($ch,CURLOPT_RETURNTRANSFER,true);
curl_setopt($ch,CURLOPT_POST,CURLOPT_POSTFIELDS,$post);

$response = curl_exec($ch);

首先,CURLOPT_POSTFIELDS的官方PHP description说：

The full data to post in a HTTP “POST”
operation. To post a file,prepend a
filename with @ and use the full path.
This can either be passed as a
urlencoded string like
‘para1=val1&para2=val2&…’ or as an
array with the field name as key and
field data as value. If value is an
array,the Content-Type header will be
set to multipart/form-data.

听起来你可以将任何类型的数组传递给POSTFIELDS吗？错误. POSTFIELDS只接受非标量值,并且在传递多维数组时会阻塞Array to string转换错误.因此,您拥有的唯一其他选项是http_build_query()您的数组能够传递不会阻塞的多维数组.

但是..正如您可以在PHP页面上的注释中看到的那样：

Note: Passing an array to
CURLOPT_POSTFIELDS will encode the
data as multipart/form-data,while
passing a URL-encoded string will
encode the data as
application/x-www-form-urlencoded.

如果将urlencoded字符串传递给POSTFIELDS,则该帖子将不会进行多部分/表单数据编码,从而导致文件上载失败.

因此,将两者与CURL结合起来似乎几乎是不可能的,如果您使用常规HTML表单则不会有问题.

我的问题是：是否有可能绕过这个奇怪的CURL怪癖来发布多维数组和文件上传？