Allowing upload only if required files are present

[Jeffrey]

I'm trying to create a scenario where the upload must contain exactly 9 files and a way to validate that each one exists.

Is there a way to grab the process, perhaps client side that would allow me perform this check? The methods I've found so far seem to operate on one file uploaded at a time rather than being to examine the entire batch before sending the files. Thanks.

[Peter Milchev]

Hello Jeffrey,

You can use the following article to prevent the postback if the validation fails (or use the .get_isUploading() method of the AsyncUpload's client-side object): 

• https://docs.telerik.com/devtools/aspnet-ajax/controls/asyncupload/how-to/prevent-page-submitting-while-uploading-file;

Regarding the validation itself, you can use the .getUploadedFiles() method of the client-side object of the AsyncUpload: 

• https://docs.telerik.com/devtools/aspnet-ajax/controls/asyncupload/client-side-programming/radasyncupload-object;

Regards,
Peter Milchev
Progress Telerik