Search Values From Gridview

Question

I have  a function where the user will upload files and save it to the root directory of my application and viewing all the files after uploading.

 

The issue that I am facing right now is how to search the data from my gridview. Please note that the data comes from a folder from my root directory. If it had been from the database, then I won't face this issue.

 

Thank you so much for your assistance.