Reading binary files with multiple headers

So far I have structs representing the data, but how would I implement something like this so that it updates 'nOffset' every time it reads the struct, and reads until the end of the file?

[StructLayout(LayoutKind.Sequential, Pack=1)]

public struct keyBiffRes

{

public string sResName;

public ushort usResType;

public uint uBifResId;

public static keyBiffRes Read(BinaryReader readKey, int nOffset)

{

keyBiffRes stKeyBiffRes = new keyBiffRes();

readKey.BaseStream.Position = nOffset;

stKeyBiffRes.sResName = new String(readKey.ReadChars(16));

stKeyBiffRes.usResType = readKey.ReadUInt16();

stKeyBiffRes.uBifResId = readKey.ReadUInt32();

return stKeyBiffRes;

}

}

Thanks in advance.