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问题二:假设abc.abc中是如下这样
abcdefgh
dim i as string *1
open "c:\abc.abc" For Binary As #1
get #1,1,i
close #1
如上代码,那么i会得到a
我如果要做成
Fgetfield(文件名,字段长度)这样的函数,以往的做法是
function Fgetfield(filename,fieldlen)
dim i1 as string *1
dim i2 as string *2
dim i3 as string *3
dim i4 as string *4
dim i5 as string *5
dim i6 as string *6
open filename For Binary As #1
select case fieldlen
case 1
get #1,1,i1
Fgetfield=i1
case 2
get #1,1,i2
Fgetfield=i2
case 3
get #1,1,i3
Fgetfield=i3
case 4
get #1,1,i4
Fgetfield=i4
case 5
get #1,1,i5
Fgetfield=i5
case 6
get #1,1,i6
Fgetfield=i6
end select
close #1
end function
这样如果最大只需要截取字符长度为6的字段,尚且可以,但如果要截取字符长度为n的字段(n是一个足够大的数,假设文件的字节数比n大),那应该怎么做?
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