谁能给我解释下这几行代码?
var
DecompressionStream :TDecompressionStream;
count, i :integer;
buf:pchar;
begin
SFile:=TMemoryStream.Create;
Sfile.LoadFromFile('ab.dat');
sfile.Read( count, sizeof(count) );
getmem(buf,count);
DecompressionStream:=TDecompressionStream.Create(sfile);
//-------上面这行不知道怎么在BCB里面用??
Decompressionstream.ReadBuffer(buf^,count);
sfile.Clear ;
sfile.WriteBuffer(buf^,count);
sfile.position:=0;
decompressionstream.free;
freemem(buf);
上面这段代码不知道做了些什么东西?有什么用?望大家解释一下