能不能简化一下...没分了 (0分)

if _xto = '0000' then Assignfile(_xtofile,'0000.xjc')
else if _xto = '0001' then Assignfile(_xtofile,'0001.xjc')
else if _xto = '0002' then Assignfile(_xtofile,'0002.xjc')
else if _xto = '0003' then Assignfile(_xtofile,'0003.xjc')
...
...
else if _xto = '1000' then Assignfile(_xtofile,'1000.xjc')
else if _xto = '1001' then Assignfile(_xtofile,'1001.xjc')
else if _xto = '1002' then Assignfile(_xtofile,'1002.xjc')
else if _xto = '1003' then Assignfile(_xtofile,'1003.xjc')
else if _xto = '1100' then Assignfile(_xtofile,'1100.xjc')
else if _xto = '1101' then Assignfile(_xtofile,'1101.xjc')
else if _xto = '1102' then Assignfile(_xtofile,'1102.xjc')
else if _xto = '1200' then Assignfile(_xtofile,'1200.xjc')
else if _xto = '1201' then Assignfile(_xtofile,'1201.xjc')
else if _xto = '1300' then Assignfile(_xtofile,'1300.xjc');
//...N个不写了...
redit2.Lines.Clear;
reset(_xtofile);
while not eof(_xtofile) do
begin
readln(_xtofile,tempstr);
redit2.Lines.Add(tempstr);
end;
end;
能不能简化一下...
没分了...

Assignfile(_xtofile,_xto+'.xjc');

谢了