中国DOS联盟

任务是：
文本a.txt文件共50000字节，把其中第3002字节改为A、3003字节改为F、3004字节改为G、3008字节改为H，字符均半角。其他字符不变。

谢谢各位帮忙！！！

OPEN "A.TXT" FOR RANDOM AS #1 LEN = 1
FIELD #1, 1 AS A$
A$ = "A"
PUT 1, 3002
A$ = "F"
PUT 1, 3003
A$ = "G"
PUT 1, 3004
A$ = "H"
PUT 1, 3008
CLOSE #1


以上这段原码只能把301、302、303、304字节替换为ASCII码为00的空（null），而不是想要的A、F、G、H

请兄弟们帮忙！！！

试试将第一行改为二进制方式：
OPEN "A.TXT" FOR BINARY AS #1

你定义变量类型或TYPE后，就可以了。修改如下，运行结果如愿！

DIM myData AS STRING * 1
OPEN "A.TXT" FOR RANDOM AS #1 LEN = 1
myData = "A"
PUT 1, 3002, myData
myData = "F"
PUT 1, 3003, myData
myData = "G"
PUT 1, 3004, myData
myData = "H"
PUT 1, 3008, myData
CLOSE #1
END

如果用JONEPENG的方法，还要作些修改：
OPEN "A.TXT" FOR BINARY AS #1
a$ = "A"
PUT 1, 3002, a$
a$ = "F"
PUT 1, 3003, a$
a$ = "G"
PUT 1, 3004, a$
a$ = "H"
PUT 1, 3008, a$
CLOSE #1
END

Last edited by 本是 on 2005-10-24 at 13:24 ]