dart - HttpRequest::getRequestHeaders似乎只返回 header 的子集？

Question

如您所见，我做了一个成功的请求。我的问题是我在下面打印的3行。

var headerList = request.getAllResponseHeaders();
print("RunTime type of Header List: ${headerList.runtimeType}");
print("Header List Count: ${headerList.length}");
print("Header List is as follows: \n$headerList");

因此，似乎要求 HttpRequest没有返回足够的信息。我希望它能返回所有 header 信息的完整字符串，k => v对的Map或数组。

好像它只获取了前64个字符。

为什么不获取所有文件？理想情况下，我正在尝试通过 request.getResponseHeader("Content-Disposition");获取“Content-Disposition” header ，但是正如您可以想象的那样，给定此信息，由于请求无法找到该信息，因此它实际上将返回null。

Answer 1

我想你需要补充
Access-Control-Expose-Headers Content-Disposition
在您的服务器上。

Access-Control-Expose-Headers (optional) - The XMLHttpRequest 2 object has a getResponseHeader() method that returns the value of a particular response header. During a CORS request, the getResponseHeader() method can only access simple response headers. Simple response headers are defined as follows:

• Cache-Control
• Content-Language
• Content-Type
• Expires
• Last-Modified
• Pragma

If you want clients to be able to access other headers, you have to use the Access-Control-Expose-Headers header. The value of this header is a comma-delimited list of response headers you want to expose to the client.

从 http://www.html5rocks.com/en/tutorials/cors/