The following code displays all the file names.
1.How to pick the files name having the format as xxxxx_yyyy.pdf
here the xxxxx is being entered from Textbox t1.
2.What ever the resultset comes should be added to Gridview1.
DirectoryInfo dir = new DirectoryInfo(MapPath("Files/"));
FileInfo files = dir.GetFiles();
ArrayList listItems = new ArrayList();
foreach (FileInfo info in files)