MailAttachment
Attachment objects allow referencing files within a Email
object.
Functions and properties
Attachment objects are created using the 4D.MailAttachment.new()
function. They provide the following functions and read-only properties:
4D.MailAttachment.new()
4D.MailAttachment.new( file : 4D.File { , name : string {, cid : string{ , type : string { , disposition : string } } } } ) : 4D.MailAttachment
4D.MailAttachment.new( zipFile : 4D.ZipFile { , name : string {, cid : string{ , type : string { , disposition :string } } } } ) : 4D.MailAttachment
4D.MailAttachment.new( blob : 4D.Blob { , name : string {, cid : string{ , type : string { , disposition :string } } } } ) : 4D.MailAttachment
4D.MailAttachment.new( path : string { , name : string {, cid : string{ , type : string { , disposition :string } } } } ) : 4D.MailAttachment
Parameter | Type | Description | |
---|---|---|---|
file | 4D.File | → | Attachment file |
zipFile | 4D.ZipFile | → | Attachment Zipfile |
blob | 4D.Blob | → | BLOB containing the attachment |
path | string | → | Path of the attachment file |
name | string | → | Name + extension used by the mail client to designate the attachment |
cid | string | → | ID of attachment (HTML messages only), or " " if no cid is required |
type | string | → | Value of the content-type header |
disposition | string | → | Value of the content-disposition header: "inline" or "attachment". |
Result | 4D.MailAttachment | ← | Attachment object |
Description
The 4D.MailAttachment.new
function allows you to create an attachment object that you can add to an Email object.
To define the attachment, you can use:
- a file, pass a
4D.File
object containing the attachment file. - a zipfile, pass a
4D.ZipFile
object containing the attachment file. - a blob, pass a
4D.Blob
object containing the attachment itself. - a path, pass a string value containing the path of the attachment file, expressed with the system syntax. You can pass a full path name or a simple file name (in which case 4D will search for the file in the same directory as the project file).
The optional name parameter lets you pass the name and extension to be used by the mail client to designate the attachment. If name is omitted and:
- you passed a file path, the name and extension of the file is used,
- you passed a BLOB, a random name without extension is automatically generated.
The optional cid parameter lets you pass an internal ID for the attachment. This ID is the value of the Content-Id
header, it will be used in HTML messages only. The cid associates the attachment with a reference defined in the message body using an HTML tag such as \<img src = "cid:ID">
. This means that the contents of the attachment (e.g., a picture) should be displayed within the message on the mail client. The final result may vary depending on the mail client. You can pass an empty string in cid if you do not want to use this parameter.
You can use the optional type parameter to explicitly set the content-type
of the attachment file. For example, you can pass a string defining a MIME type ("video/mpeg"). This content-type value will be set for the attachment, regardless of its extension. For more information about MIME types, please refer to the MIME type page on Wikipedia.
By default, if the type parameter is omitted or contains an empty string, the content-type
of the attachment file is based on its extension. The following rules are applied for the main MIME types:
Extension | Content Type |
---|---|
jpg, jpeg | image/jpeg |
png | image/png |
gif | image/gif |
application/pdf | |
doc | application/msword |
xls | application/vnd.ms-excel |
ppt | application/vnd.ms-powerpoint |
zip | application/zip |
gz | application/gzip |
json | application/json |
js | application/javascript |
ps | application/postscript |
xml | application/xml |
htm, html | text/html |
mp3 | audio/mpeg |
other | application/octet-stream |
The optional disposition parameter lets you pass the content-disposition
header of the attachment. You can pass one of the following constants:
Constant | Value | Comment |
---|---|---|
kMailDispositionAttachment | "attachment" | Set the Content-disposition header value to "attachment", which means that the attachment file must be provided as a link in the message. |
kMailDispositionInline | "inline" | Set the Content-disposition header value to "inline", which means that the attachment must be rendered within the message contents, at the "cid" location. The rendering depends on the mail client. |
By default, if the disposition parameter is omitted:
- if the cid parameter is used, the
Content-disposition
header is set to "inline", - if the cid parameter is not passed or empty, the
Content-disposition
header is set to "attachment".
Example
You want to send an email with a file as an attachment and an image embedded in the HTML body:
var attachment : 4D.File
var email,server : object
var transporter : 4D.SMTPTransporter
attachment = file("/PACKAGE/Docs/cv-john-smith.pdf")
server = newObject
server.host = "smtp.mail.com"
server.user = "test_user@mail.com"
server.password = "p@ssw@rd"
transporter = 4D.SMTPTransporter.new(server)
email = newObject
email.from = "test_user@mail.com"
email.to = "test_user@mail.com"
email.subject = "This is a test message with attachments"
//add a link to download file
email.attachments = newCollection(4D.MailAttachment.new(attachment))
//insert an inline picture (use a cid)
email.attachments[1] = 4D.MailAttachment.new(file("/PACKAGE/Docs/photo.jpg"),"","Qodly")
email.htmlBody = "<html>"+\
"<body>Hello World!"+\
"<img src = 'cid:Qodly' >"+\
"</body>"+\
"</head>"+\
"</html>"
transporter.send(email) //send mail
.cid
.cid : string
Description
The .cid
property contains the ID of the attachment. This property is used in HTML messages only. If this property is missing, the file is handled as a simple attachment (link).
.disposition
.disposition : string
Description
The .disposition
property contains the value of the Content-Disposition
header. Two values are available:
- "inline": the attachment is rendered within the message contents, at the "cid" location. The rendering depends on the mail client.
- "attachment": the attachment is provided as a link in the message.
.getContent()
.getContent() : 4D.Blob
Parameter | Type | Description | |
---|---|---|---|
Result | 4D.Blob | ← | Content of the attachment |
Description
The .getContent()
function returns the contents of the attachment object in a 4D.Blob
object. You can use this method with attachment objects received by the mailConvertFromMIME
command.
.name
.name : string
Description
The .name
property contains the name and extension of the attachment. By default, it is the name of the file, unless another name was specified in the 4D.MailAttachment.new()
command.
.path
.path : string
Description
The .path
property contains the POSIX path of the attachment file, if it exists.
.platformPath
.platformPath : string
Description
The .platformPath
property returns the path of the attachment file expressed with the current platform syntax.
.type
.type : string
Description
The .type
property contains the content-type
of the attachment file. If this type is not explicitly passed to the 4D.MailAttachment.new()
command, the content-type
is based on its file extension.