Handling file upload

If you have form like following snippet

<form action="/submit" method="post" enctype="multipart/form-data">
    <input type="file" name="myFile">
    <button type="submit">Submit</button>
</form>

To retrieve file uploaded by client, you need to call getUploadedFile() method from IRequest interface. It returns data of type IUploadedFileArray which array of IUploadedFile instance. Please read Working with request for information how to work with request object.

var myFile : IUploadedFileArray;
...
myFile := request.getUploadedFile('myFile');

Client can send one or more file with same name, for example:

<form action="/submit" method="post" enctype="multipart/form-data">
    <input type="file" name="myFile">
    <input type="file" name="myFile">
    <button type="submit">Submit</button>
</form>

If client upload one or more files, length(myFile) will indicates how many files actually uploaded.

Move uploaded file

Initially, uploaded file will be stored in system temporary directory. You need to call moveTo() methods to move into permanent location.

if (length(myFile) > 0) then
begin
    myFile[0].moveTo(targetUploadPath);
end;

targetUploadPath is full filename (including its target directory). You must make sure that targetUploadPath is writeable. Exception EInOutError is raised when uploaded file can not be written to target path.

If you do not call moveTo(), at the end of request handling, temporary uploaded file will be deleted.

Get uploaded file size

Size of uploaded file in octet (or bytes) can be queried with size() method.

var fSize : int64;
...
fSize := myFile[0].size();

Get file MIME type

MIME type of uploaded file can be queried with getClientMediaType() method. For example, if upload JPEG image, you may get image/jpeg.

var mime : string;
...
mime := myFile[0].getClientMediaType();

If client does not send any MIME type (aka Content Type) then it is assumed application/octet-stream.

Get original file name

To get original file name of uploaded file use getClientFilename() method.

var filename : string;
...
filename := myFile[0].getClientFilename();

If client does not send filename then it returns empty string.

File Upload Validation

Fano Framework validation feature provides several built-in validation rules you can use to validate against file upload, such as, to verify that field is indeed a file upload, to verify that file upload match certain MIME type or more advanced use, such as, antivirus scan validation or file format validation.

Example demo

For example application that demonstrates how to handle file upload with Fano Framework, see Fano Upload. While Fano Scgi Upload example shows how to validate file being uploaded using various validation rules.

Explore more

Documentation