pb读文件

string ls_log_path,ls_txt
string ls_rtn
ls_log_path=idt_card.is_imgfile
long ll_file

ll_file=fileopen(ls_log_path,linemode!,Read!,LockWrite!,Append! )
ll_rtn=fileread(ll_file,ls_txt)
do while ll_rtn>=0
ls_rtn+=ls_txt
ll_rtn=fileread(ll_file,ls_txt)
loop
fileclose(ll_file)