Attachment submission format
When attachments are enabled, HTML5 form submits multipart data. The multi-part submission data has two parts dataXml and attachments.
For backward compatibility, if
mfAllowAttachments
option is turned off, then the HTML5 forms does not send the multi-part data. It sends simple data xml in application/xml format.If the mfAllowAttachments flag is turned on, the submit service proxy service also posts multipart data with dataXml and attachments.
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