应该是可能的：这里有一个表格，通过浏览器发布（省略不相关的字段）：

POST http://host.example.com/somewhere HTTP/1.1
Content-Type: multipart/form-data; boundary=---------------------------7da16b2e4026c
Content-Length: 105732

-----------------------------7da16b2e4026c
Content-Disposition: form-data; name="NewFile"; filename="test.jpg"
Content-Type: image/jpeg

(...raw JPEG data here...)
-----------------------------7da16b2e4026c
Content-Disposition: form-data; name="otherformfield"

content of otherformfield is this text
-----------------------------7da16b2e4026c--

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因此，如果我们自己构建POST主体并设置一两个额外的头，我们应该能够模拟这一点：

// form field separator
$delimiter = '-------------' . uniqid();
// file upload fields: name => array(type=>'mime/type',content=>'raw data')
$fileFields = array(
    'file1' => array(
        'type' => 'text/plain',
        'content' => '...your raw file content goes here...'
    ), /* ... */
);
// all other fields (not file upload): name => value
$postFields = array(
    'otherformfield'   => 'content of otherformfield is this text',
    /* ... */
);

$data = '';

// populate normal fields first (simpler)
foreach ($postFields as $name => $content) {
   $data .= "--" . $delimiter . "\r\n";
    $data .= 'Content-Disposition: form-data; name="' . $name . '"';
    // note: double endline
    $data .= "\r\n\r\n";
}
// populate file fields
foreach ($fileFields as $name => $file) {
    $data .= "--" . $delimiter . "\r\n";
    // "filename" attribute is not essential; server-side scripts may use it
    $data .= 'Content-Disposition: form-data; name="' . $name . '";' .
             ' filename="' . $name . '"' . "\r\n";
    // this is, again, informative only; good practice to include though
    $data .= 'Content-Type: ' . $file['type'] . "\r\n";
    // this endline must be here to indicate end of headers
    $data .= "\r\n";
    // the file itself (note: there's no encoding of any kind)
    $data .= $file['content'] . "\r\n";
}
// last delimiter
$data .= "--" . $delimiter . "--\r\n";

$handle = curl_init($url);
curl_setopt($handle, CURLOPT_POST, true);
curl_setopt($handle, CURLOPT_HTTPHEADER , array(
    'Content-Type: multipart/form-data; boundary=' . $delimiter,
    'Content-Length: ' . strlen($data)));  
curl_setopt($handle, CURLOPT_POSTFIELDS, $data);
curl_exec($handle);

型
这样，我们就可以自己做所有的繁重工作，并相信cURL不会把它搞砸。

PHP可以访问一个临时位置“php：//memory”，这实际上使您尝试做的事情相当容易。

$fileHandle = fopen('php://memory', 'rw');
fwrite($fileHandle, $content);
rewind($fileHandle);

$options = array(
    CURLOPT_RETURNTRANSFER  => true
    ,CURLOPT_SSL_VERIFYPEER => false
    ,CURLOPT_SSL_VERIFYHOST => 1
    ,CURLOPT_HTTPHEADER     => array(
        'Content-type: multipart/form-data',
    )
    ,CURLOPT_INFILE         => $fileHandle
    ,CURLOPT_INFILESIZE     => strlen($content)
);

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