php 文件流提交 没有使用圈a形式

//图片url地址

$pic_url = "http://img.adbox.sina.com.cn/pic/1505759360-1398150715642.jpg";

$api_url = "http://upload.admin.mp.sina.com.cn/mpimg/index.php?show_type=json";

$delimiter = "-------------" . uniqid();

$delimiter = md5(time());

$fileFields = array(

"mpImageFile" => array(

"type" => "image/jpg",

"content" => file_get_contents($pic_url),

)

);

$postFields = array(

"uid" => "1764439395",

"srctype" => "1"

);

$data = "";

foreach ($postFields as $name => $content) {

$data .= "--" . $delimiter . " ";

$data .= "Content-Disposition: form-data; name="" . $name . "";". " "; ;

$data .= " ";

$data .= $content . " ";

}

foreach ($fileFields as $name => $file) {

$data .= "--" . $delimiter . " ";

$data .= "Content-Disposition: form-data; name="" . $name . "";" ." filename="" . $name . """ . " ";

$data .= "Content-Type: " . $file["type"] . " ";

$data .= " ";

$data .= $file["content"] . " ";

}

$data .= "--" . $delimiter . "-- ";

$handle = curl_init($api_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);