[](http://www.uploadify.com) # onOpen Input Type:**function** Input Format:**function(event,ID,fileObj) {}** Required:**optional** The **onOpen** option allows you to fire a custom function when a file is opened for upload. There is no default function for this option. Due to synchronicity issues, changing the **scriptData** via the **.uploadifySettings()** method will not work properly inside an onOpen custom function. ### Arguments **event **The event object.**** **ID **The unique identifier of the file that was opened.**** **fileObj **An object containing details about the file that was****opened.** ** - **[name]** 每 The name of the file**** - **[size]** 每 The size in bytes of the file**** - **[creationDate]** 每 The date the file was created**** - **[modificationDate]** 每 The last date the file was modified**** - **[type]** 每 The file extension beginning with a '.' ### Demo Javascript Code 1. $('#file_upload').uploadify({ 1.   'uploader'    : '/uploadify/uploadify.swf', 1.   'script'      : '/uploadify/uploadify.php', 1.   'cancelImg'   : '/uploadify/cancel.png', 1.   'folder'      : '/uploads', 1.   'onOpen'      : function(event,ID,fileObj){ 1.       $('#uploader_message').text('The upload is beginning for ' + fileObj.name); 1.     } 1. }); HTML Code 1. <inputtype="file"id="file_upload"name="file_upload"/> 1. <divid="uploader_message"></div> 1. <ahref="javascript:$('#file_upload').uploadifyUpload();">Upload Files</a> [Upload Files](#) [](#) Help keep Uploadify free and support the development of other excellent apps!  [home](#)  |  [about](#)  |  [download](#)  |  [demos](#)  |  [documentation](#)  |  [faqs](#)  |  [forums](#) ©2011 by [Reactive Apps](http://www.reactiveapps.com)