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diff --git a/guide/multipart_intro.md b/guide/multipart_intro.md deleted file mode 100644 index dde4099..0000000 --- a/guide/multipart_intro.md +++ /dev/null @@ -1,53 +0,0 @@ -Introduction to multipart -========================= - -Multipart originates from MIME, an Internet standard that -extends the format of emails. Multipart messages are a -container for parts of any content-type. - -For example, a multipart message may have a part -containing text and a second part containing an -image. This is what allows you to attach files -to emails. - -In the context of HTTP, multipart is most often used -with the `multipart/form-data` content-type. This is -the content-type you have to use when you want browsers -to be allowed to upload files through HTML forms. - -Multipart is of course not required for uploading -files, it is only required when you want to do so -through HTML forms. - -Structure ---------- - -A multipart message is a list of parts. Parts may -contain either a multipart message or a non-multipart -content-type. This allows parts to be arranged in a -tree structure, although this is a rare case as far -as the Web is concerned. - -Form-data ---------- - -In the normal case, when a form is submitted, the -browser will use the `application/x-www-form-urlencoded` -content-type. This type is just a list of keys and -values and is therefore not fit for uploading files. - -That's where the `multipart/form-data` content-type -comes in. When the form is configured to use this -content-type, the browser will use one part of the -message for each form field. This means that a file -input field will be sent in its own part, but the -same applies to all other kinds of fields. - -A form with a text input, a file input and a select -choice box will result in a multipart message with -three parts, one for each field. - -The browser does its best to determine the content-type -of the files it sends this way, but you should not -rely on it for determining the contents of the file. -Proper investigation of the contents is recommended. |