Prevent repeated file upload

Question

How can i prevent the user from uploading the same file or programmatically check if the filename already exists. Its an application requirement the filename to be unique. Since im storing the data of the file in a dictionary and using the filename as key.

Yohapuja Selvakumaran · Answer

Hi jose,Thank you for contacting us. We
are delighted to inform you that you can restrict the file from uploading if the same file is already uploaded by using the select event with the args.Cancel
set to true. We have prepared a sample that specifically addresses your
requirement to demonstrate how this can be achieved. Please refer to the
attached sample for more information.Code Snippet

public void SuccessHandler(SuccessEventArgs args)
      {
          uploadedFiles.Add(args.File.Name);
      }
      public void SelectHandler(SelectedEventArgs args)
      {
          string selectedfile =
  args.FilesData[0].Name;
          if
  (uploadedFiles!=null && uploadedFiles.Contains(selectedfile))
          {
              args.Cancel = true;
          }
      }

Regards,Yohapuja SAttachment: FileUpload_Repeat_3c1186ea.zip

Hüseyin · Answer

Hello,When we set args.Cancel true, the uploader clears the entire list. Shouldn't it just delete the duplicate file from the list? I am asking for your urgent help on this matter. Thank you from now.

Yohapuja Selvakumaran · Answer

Hi HuseyinWe apologize for the delay in getting back to you. In the
provided sample, the prevention of uploading duplicate files only ensures that
duplicate files are not added to the list. It does not clear the entire list of
files. Kindly check out the below gif image. We kindly request further clarification regarding your
concern. To assist you more effectively, could you please provide the following
details:Video Illustration: Could you share a video
illustrating the issue you're experiencing? This will help us better understand
the scenario and the specific behavior you're encountering.Scenarios for Entire File Clearing: Please specify
the scenarios or conditions in which the entire file list should be cleared.
Understanding these specific scenarios will aid us in addressing your issue
accurately.Regards,Yohapuja
SAttachment: FileUpload_Repeat_3c1186ea_556cca56.zip

Jenia · Answer

Good afternoon, what @huseyin mentions is that it is not working with AutoUpload="true" I am using version 24.2.3.

Yohapuja Selvakumaran · Answer

Hi Jenia,We have considered the reported issue “When using
auto upload as true and preventing the duplicate file in the select event, the
file list is cleared" as a bug from our end and the fix for the issue will be included with our upcoming weekly release on March 27th, 2024.Now
you can track the status of the reported issue through the feedback below,Feedback Link: https://www.syncfusion.com/feedback/51905/when-using-auto-upload-as-true-and-preventing-the-duplicate-file-in-the-select
Disclaimer: “Inclusion of this solution in the
weekly release may change due to other factors including but not limited to QA
checks and works reprioritization.”Regards,Yohapuja S

Yohapuja Selvakumaran · Answer

Hi Jose,We
have included the fix for the issue “When using auto upload as true and preventing the
duplicate file in the select event, the file list is cleared " with
our package version “25.1.38”. Therefore, we recommend upgrading to our latest
version to resolve the current issue. Kindly check out the below upgraded
sample.Rootcause: The IsShowFileList property was set to false when preventing a
file in a selected event, unintentionally hiding the file list. However, this
prevented both new and existing files from being visible. To resolve this, the
property was removed. Moving forward, it's essential to ensure consistent file
list visibility by refining the logic and conducting thorough testing.Sample: https://blazorplayground.syncfusion.com/hZVJZTXuCFwadKjo
Release Notes: https://blazor.syncfusion.com/documentation/release-notes/25.1.37?type=all#uploader
Regards,Yohapuja S