OnFormDataSubmit Property

Gets or sets the OnFormDataSubmit client side event. It is fired before submitting to the server the uploading file(and its additional data if any). It could be used to append additional data fields to the FormData object(if the browser supports HTML5 file API - like newest Chrome, Firefox, IE11+). If the browser does not support HTML5 file API(IE10 and older) it could be added these data fields(as hidden input fields) to the form. Use the public API function addDataFields.

'Declaration
 
Public Property OnFormDataSubmit As String

public string OnFormDataSubmit {get; set;}