控制写文件的次数Appendfile

写文件记录，用什么方法控制是唯一的一条记录；记录了多条；

If(MarketPosition==0 and    AMA1[1]>AMA2[1]   )   
   {  BUY(0,OPEN);
   CTR1=0;
   }
                 
     If(MarketPosition==1 and    AMA1[1]<AMA2[1]   )   
   { fileENtry=EntryPrice;FileTime1=FileTime0;FileDate1=FileDate0;
   Sell(0,OPEN); 
   
   
   IF( CTR1==0  )
 {
  CTR1=1;
  FileAppend("D:\\aaa",  TEXT(FileDate1)+","+ TEXT(FileTime1)+","+ SymbolName+    "fileENtry"+Text(fileENtry) +","+TEXT(Open ) );}
             
   
   }
    If(MarketPosition==0 and    AMA1[1]<AMA2[1]   )   
   { SellShort(0,OPEN);
   CTR1=0;
   }
                 
     If(MarketPosition==-1 and    AMA1[1]>AMA2[1]   )   
   { fileENtry=EntryPrice;FileTime1=FileTime0;FileDate1=FileDate0;
   BuyToCover(0,OPEN); 
 IF( CTR1==0  )
 {
  CTR1=1;
  FileAppend("D:\\aaa",  TEXT(FileDate1)+","+ TEXT(FileTime1)+","+ SymbolName+    "fileENtry"+Text(fileENtry) +","+TEXT(Open ) );}