問題描述

我有一個發送一些數據的 AJAX 請求.數據尊重 multipart/form-data 規范.

I have an AJAX request that sends out some data. The data respects the multipart/form-data specification.

我面臨的問題是瀏覽器將 Content-Type 標頭設置為 text/plain 并且它應該是 multipart/form-data.

The problem I'm facing is that the browser sets the Content-Type header to text/plain and it should be multipart/form-data.

我試過這樣做:request.setRequestHeader("Content-Type", "multipart/form-data"); 但這會發出 400 Bad Request 錯誤.

I've tried doing this: request.setRequestHeader("Content-Type", "multipart/form-data"); but this gives out an 400 Bad Request error.

如果我這樣做 request.setRequestHeader("Content-Typexxxx", "multipart/form-data"); 沒有錯誤，則設置了Content-Typexxxx"標頭，但顯然是對我沒有幫助.

If I do request.setRequestHeader("Content-Typexxxx", "multipart/form-data"); there is no error, the "Content-Typexxxx" header is set but it obviously is no help to me.

我猜有一個可以設置的有效 Content-Type 標頭列表，multipart/form-data"不在其中，但我找不到解決我的困境的方法.

I guess there is a list of valid Content-Type headers one can set and "multipart/form-data" isn't among them, but I cannot find a sollution to my predicament.

實際發送的數據示例:

Content-Type: multipart/form-data; boundary=l3iPy71otz

--l3iPy71otz
Content-Disposition: form-data; name="titluPublic"

Variation_1
--l3iPy71otz
Content-Disposition: form-data; name="nr_versiune"


--l3iPy71otz--

謝謝！

推薦答案

你沒有在請求頭中設置boundary，如:

You didn't set the boundary in your request header, as in:

request.setRequestHeader("Content-Type", "multipart/form-data; boundary=l3iPy71otz");

有關詳細信息，請參閱 RFC 2045:

For more information, see RFC 2045:

5 內容類型標題字段
[…]
參數是媒體的修飾符子類型，因此不要從根本上影響性質內容.有意義的集合參數取決于媒體類型和亞型.大多數參數是與單個特定的相關聯亞型.然而，一個給定的頂級媒體類型可以定義適用的參數該類型的任何子類型.參數可能需要他們的定義內容類型或子類型，或者它們可能是選修的.MIME 實現必須忽略其名稱的任何參數不認識.

5 Content-Type Header Field
[…]
Parameters are modifiers of the media subtype, and as such do not fundamentally affect the nature of the content. The set of meaningful parameters depends on the media type and subtype. Most parameters are associated with a single specific subtype. However, a given top-level media type may define parameters which are applicable to any subtype of that type. Parameters may be required by their defining content type or subtype or they may be optional. MIME implementations must ignore any parameters whose names they do not recognize.

例如，字符集"參數適用于任何子類型文本"，而邊界"任何子類型都需要參數多部分"媒體類型.

For example, the "charset" parameter is applicable to any subtype of "text", while the "boundary" parameter is required for any subtype of the "multipart" media type.

更新:我發現的另一個問題 on the net 當 charset 添加到 Content-type 時出現code> 在請求標頭中，但不在正文中的消息邊界中(這也適用于您的測試用例).這似乎不是一個可行的解決方案，但也許會有所幫助.

data.params += "--" + data.uniqid + "; charset=UTF-8" + data.crlf;
…
request.setRequestHeader("Content-Type", "multipart/form-data; boundary=" + data.uniqid + "; charset=UTF-8");

data.params = "Content-Type: multipart/form-data; boundary=" + data.uniqid;
…
data.params += "--" + data.uniqid + data.crlf;
…
data.params += "--" + data.uniqid + "--";
…
request.setRequestHeader("Content-Type", "multipart/form-data; charset=UTF-8; boundary=" + data.uniqid);