HTTP post multipart-form 数据长度格式？

Question

在 HTTP POST 多部分形式的内容类型流中，长 -------------- 行是什么意思？这些行末尾的十六进制编码是什么？你能从中算出变量的长度吗？或者这是一个特别设计的序列，以便您可以找到变量之间的中断？

-----------------------------7dc34719970524 
Content-Disposition: form-data; name="my variable" 

blah content here
-----------------------------7dc34719970524 
Content-Disposition: form-data; name="asdfasdf"

heaps of data here

Answer 1

它是一个边界，用于在多部分数据提交的情况下分隔不同的数据集。阅读更多相关信息:

http://www.w3.org/Protocols/rfc1341/7_2_Multipart.html

引用链接:

In the case of multiple part messages, in which one or more different sets of data are combined in a single body, a "multipart" Content-Type field must appear in the entity's header. The body must then contain one or more "body parts," each preceded by an encapsulation boundary, and the last one followed by a closing boundary. Each part starts with an encapsulation boundary, and then contains a body part consisting of header area, a blank line, and a body area. Thus a body part is similar to an RFC 822 message in syntax, but different in meaning.