B4X

The MIME Content-Type Header Field

See more MIME Examples

Explains the ContentType property and the Content-Type header field including the various attributes that may be included. B4X

Dim success As Boolean = False

'  Every part in a MIME messsage should include a Content-Type header field.
'  The Content-Type indicates the type of content contained in the MIME part.
'  For example: text/plain, image/jpeg, application/pdf, application/json, multipart/mixed, etc.

'  Multipart content types are those where the MIME part's body is composed of N inner MIME messages,
'  separated by a boundary string.
'  This is how MIME gets a nested, tree-like structure.  The most common multipart MIME types
'  are (for email related MIME) multipart/mixed, multipart/alternative, and multipart/related,
'  and for HTTP related MIME, it is multipart/form-data.

Dim mime As ChilkatMime
mime.Initialize

'  The Content-Type header field can be set or modified in two ways.
'  1) By setting the ContentType, Micalg, Name, Charset, Boundary, or Protocol properties.
'     Setting the ContentType property sets the primary value (such as "text/plain") of the header field.
'     Each of the other properties listed above will replace or add a particular attribute value.

'  2) By setting the entire contents of the ContentType header with the SetHeaderField method.
'     This updates each of the Content-Type related properties.

'  For example:
mime.ContentType = "text/plain"
mime.Charset = "utf-8"

'  The Content-Type header field contains this:
'      Content-Type: text/plain; charset=utf-8
Log(mime.GetEntireHead)
Log("-")

mime.SetHeaderField("Content-Type", "image/jpeg; name=" & Chr(34) & "kitty.jpg" & Chr(34))
'  The Content-Type header field now contains this:
'      Content-Type: image/jpeg; name="kitty.jpg"
Log(mime.GetEntireHead)
Log("-")

'  Notice how the properties have been updated:
Log("ContentType property: " & mime.ContentType)
Log("Charset property: " & mime.Charset)
Log("Name property: " & mime.Name)
Log("-")

'  To change a particular attribute value, set the property.
mime.Name = "doggy.jpg"
Log(mime.GetEntireHead)
Log("-")

'  To remove an attribute value from the Content-Type header,
'  set the property to an empty string.
mime.Name = ""
Log(mime.GetEntireHead)
Log("-")