使用正确的文件名将gridview导出为excel

I have a code that will loop through each row and each column and export the data to excel. It is all working fine. When the user clicks on "open" file, the system is opening file with different filename. If I give the filename as "test.xls", it is opening the file as "test[1].xls". Is there a way to export with the same filename? Because of this, we are not able to use some excel functionality.I have a code that will loop through each row a