Returns true if the given file exists SysUtils unit
 function FileExists ( const FileName : string ) : Boolean;
The FileExists function returns True if the given FileName file exists.
The file is searched for in the current directory.
False may be returned if the user is not authorised to see the file.
Related commands
FileSearch Search for a file in one or more directories
FileSize Gives the size in records of an open file
FileGetAttr Gets the attributes of a file
FileSetAttr Sets the attributes of a file
Example code : Check for a file before and after deleting it
  fileName : string;
  myFile   : TextFile;
  data     : string;

  // Try to open a text file for writing to
  fileName := 'Test.txt';
  AssignFile(myFile, fileName);

  // Write to the file
  Write(myFile, 'Hello World');

  // Close the file

  // Reopen the file in read mode

  // Display the file contents
  while not Eof(myFile) do
    ReadLn(myFile, data);

  // Close the file for the last time

  // Now see if the file exists
  if FileExists(fileName)
  then ShowMessage(fileName+' exists OK')
  else ShowMessage(fileName+' does not exist');

  // Delete the file and look again
  if FileExists(fileName)
  then ShowMessage(fileName+' still exists!')
  else ShowMessage(fileName+' no longer exists');
Show full unit code
   Hello World
   Test.txt exists OK
   Test.txt no longer exists