WebFileUploader.MultiSelect

From Xojo Documentation

Property (As Boolean )
aWebFileUploader.MultiSelect = newBooleanValue
or
BooleanValue = aWebFileUploader.MultiSelect

New in 2018r1

Supported for all project types and targets.

When True, you can select multiple files when using the file chooser to select files to upload. When False you can only select a single file at a time in the file chooser. Regardless you can always have more than one file in the uploader control itself.

Notes

In order to select more than one file, you will need to hold the appropriate modifier key (Command on macOS, Control on Windows/Linux).