2
我試圖將舊的Delphi
應用程序轉換爲C#
。它做了一些binary files
通過packed records
我寫下的東西。但是,只有BInfoRec
record
保證在文件中並首先出現。其他人可能或不可能在那裏,他們的順序是未知的。特別是我遇到了一種方法的麻煩。它通過FileStream.Read
獲取正在讀入的字節數,並將其讀入packed records
之一。然後,在第一個if
語句中(在delphi版本中),它在堆上分配內存,並執行與之前相同的操作,但將其讀入指針。我試圖找出解決這個問題的最佳方法,但我絕不是Delphi的專家。轉換德爾福指針和stream.Read到C#
Delphi代碼:
StartP = packed record
x:SmallInt;
y:SmallInt;
end;
InfoP = packed record
Ycoord:double;
Xcoord:double;
//other vars here
end;
HeadP = packed record
NumP:DWORD;
SizeStruct:DWORD;
SizePoStruct:DWORD;
//other vars here
end;
BInfoRec = packed record
StructNum : WORD ;
in_size : WORD ;
//other variables here
end;
var
tStream:TFileStream;
bInfo:BInfoRec;
RestOfBFile:Pointer;
sizeofRest:Integer;
Function LoadBFile(FileName:String):Boolean;
var
sizeread:Integer;
begin
Try
LoadBFile:=False;
tStream:=TFileStream.Create(Filename,fmOpenRead);
sizeofRest:=tStream.Size-Sizeof(bInfo);
sizeread:=tStream.Read(bInfo,Sizeof(bInfo));
if sizeread = Sizeof(bInfo) then
begin //best way to convert this?
RestOfBFile:=AllocMem(sizeofRest);
sizeread:=tStream.Read(RestOfBFile^,sizeofRest);
if SizeofRest= SizeRead then
LoadBFile:=True;
end;
tStream.Free;
except
LoadBFile:=False;
tStream.Free;
end;
end;
C#(我至今):
[Serializable()]
[StructLayout(LayoutKind.Sequential, Pack = 1, CharSet = CharSet.Ansi)]
public struct StartP
{
public short x;
public short y;
}
[StructLayout(LayoutKind.Sequential, Pack = 1, CharSet = CharSet.Ansi)]
public struct InfoP
{
public double Ycoord;
public double Xcoord;
//other vars here
}
[StructLayout(LayoutKind.Sequential, Pack = 1, CharSet = CharSet.Ansi)]
public struct HeadP
{
public UInt32 NumP;
public UInt32 SizeStruct;
public UInt32 SizePoStruct;
//other vars here
}
[StructLayout(LayoutKind.Sequential, Pack = 1, CharSet = CharSet.Ansi)]
public struct BInfoRec
{
public ushort StructNum;
public ushort in_size;
}
BInfoRec bInfo;
int sizeOfRest;
private Boolean LoadBFile(string fileName)
{
int sizeRead;
byte[] buffer = new byte[Marshal.SizeOf(bInfo)];
try
{
using (var stream = new FileStream(fileName, FileMode.Open, FileAccess.Read, FileShare.None))
{
sizeOfRest = (int)stream.Length - Marshal.SizeOf(typeof(BInfoRec));
sizeRead = stream.Read(buffer, 0, Marshal.SizeOf(typeof(BInfoRec)));
if (sizeRead == Marshal.SizeOf(typeof(BInfoRec)))
{
//what goes here??
if (sizeOfRest == sizeRead)
{
return true;
}
}
}
}
catch (Exception ex)
{
return false;
}
}
我在想創造未知大小的一個新的字節數組,並使用BinaryReader
在讀然後只是檢查文件的大小。不知道這是否是最好的方法?