Help reading a binary file
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I need to read a binary file into a ushort array. The file was created with another app, and just consists of two bytes per ushort (big endian). FileStream.Read will get the bytes in OK - as bytes. I'd like to read them in directly to ushort. Sounds simple. Is it?
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I need to read a binary file into a ushort array. The file was created with another app, and just consists of two bytes per ushort (big endian). FileStream.Read will get the bytes in OK - as bytes. I'd like to read them in directly to ushort. Sounds simple. Is it?
David Williams wrote: I'd like to read them in directly to ushort. Sounds simple. Is it? It does sound simple, especially if you see how a mapping of the will look. Unfortunately there is no direct way. I would make a class deriving from FileStream and overload the Read method with some thing like this:
public ushort ReadUShort()
{
return (ushort) ((ReadByte() << 8) + ReadByte()); //not sure about my bit operations also order :zzz: CHECK IT!
}public int Read( ushort[] buffer, int offset, int length)
{
Position += offset;
int i = 0;
if (CanRead) {
for (; i < length; i++)
{
buffer[i] = ReadUShort();
}
}
return i;
}You can try that, someone might have an easier idea :~ Hope this helps :) Give them a chance! Do it for the kittens, dear God, the kittens! As seen on MS File Transfer: Please enter an integer between 1 and 2.
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I need to read a binary file into a ushort array. The file was created with another app, and just consists of two bytes per ushort (big endian). FileStream.Read will get the bytes in OK - as bytes. I'd like to read them in directly to ushort. Sounds simple. Is it?
Check out
BinaryFormatter.DeserializeI'm pretty sure that will do the job for you. Paul -
Check out
BinaryFormatter.DeserializeI'm pretty sure that will do the job for you. PaulThe formatters are used for serializing and deserializing classes/structures to and from streams. They also write and read an extra header that tells the runtime what type of object is in the stream and what name (if any) it has. To sum it up; the formatter can't be used unless it was used to create the data.
James Sig code stolen from David Wulff
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The formatters are used for serializing and deserializing classes/structures to and from streams. They also write and read an extra header that tells the runtime what type of object is in the stream and what name (if any) it has. To sum it up; the formatter can't be used unless it was used to create the data.
James Sig code stolen from David Wulff
Daaamn! That's very cool... but slightly annoying if it's not what you want :laugh: Paul
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David Williams wrote: I'd like to read them in directly to ushort. Sounds simple. Is it? It does sound simple, especially if you see how a mapping of the will look. Unfortunately there is no direct way. I would make a class deriving from FileStream and overload the Read method with some thing like this:
public ushort ReadUShort()
{
return (ushort) ((ReadByte() << 8) + ReadByte()); //not sure about my bit operations also order :zzz: CHECK IT!
}public int Read( ushort[] buffer, int offset, int length)
{
Position += offset;
int i = 0;
if (CanRead) {
for (; i < length; i++)
{
buffer[i] = ReadUShort();
}
}
return i;
}You can try that, someone might have an easier idea :~ Hope this helps :) Give them a chance! Do it for the kittens, dear God, the kittens! As seen on MS File Transfer: Please enter an integer between 1 and 2.
Yep. This works, and you do have the bit ops correct. Thanks:)
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Daaamn! That's very cool... but slightly annoying if it's not what you want :laugh: Paul
Yeah, I tried the deserialize and found it needed a header. Just to see what it needed, I serialized a 10 byte binary file and found the binary formatter put 28 bytes of header up front. Oh, well. lippie's solution works. Thanks for the response, though.;)
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Yep. This works, and you do have the bit ops correct. Thanks:)
David Williams wrote: Yep. This works, and you do have the bit ops correct. Thanks Cool :) I remembered I saw something like << 16 for Int32 , so the guess was made accordingly :wtf: hehe. However, the way I did it may not be (and probably is not) efficient. You maybe use the Encoding class (UTF8 and Unicode (BigEndian) ) in a reverse fashion, it sounds a lot like you are dealing with a UTF8 to Unicode(BigEndian) conversion. Alternatively, the more "dangerous" way is to use a bit of marshalling, remember what I said about the way the data is laid out in memory. So make a small converter.
ushort[] ConvertToUShortArray( byte[] array)
{
int size = Marshal.SizeOf(typeof(byte)) * array.Length;
ushort[] output = new ushort[array.Length/2];
IntPtr ptr = Marshal.AllocHGlobal(size);
Marshal.Copy(array, 0, ptr, array.Length);
Marshal.PtrToStructure(ptr, output); //hope this works ??
Marshal.FreeHGlobal(ptr);
return (ushort[])output;
}Ugly!! but efficient :) Hope this helps :) Give them a chance! Do it for the kittens, dear God, the kittens! As seen on MS File Transfer: Please enter an integer between 1 and 2.
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I need to read a binary file into a ushort array. The file was created with another app, and just consists of two bytes per ushort (big endian). FileStream.Read will get the bytes in OK - as bytes. I'd like to read them in directly to ushort. Sounds simple. Is it?
I think the easiest thing to do is to use a BinaryReader, and just call ReadUInt16().
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I think the easiest thing to do is to use a BinaryReader, and just call ReadUInt16().
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So it is simple :) Give them a chance! Do it for the kittens, dear God, the kittens! As seen on MS File Transfer: Please enter an integer between 1 and 2.
No, not simple. Gunnerson's BinaryReader works, but for little endian, not big. :((
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I think the easiest thing to do is to use a BinaryReader, and just call ReadUInt16().
This works for little endian. Will it work for big endian if I call it thus: 16IntURead() ;)
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This works for little endian. Will it work for big endian if I call it thus: 16IntURead() ;)
I think the answer to that would be "no". You'd need to call ReadUInt16FlipFlopBytes()... If you need to do this, you can either do the byte flip yourself, or you may be able to use the IPAddress class.
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David Williams wrote: I'd like to read them in directly to ushort. Sounds simple. Is it? It does sound simple, especially if you see how a mapping of the will look. Unfortunately there is no direct way. I would make a class deriving from FileStream and overload the Read method with some thing like this:
public ushort ReadUShort()
{
return (ushort) ((ReadByte() << 8) + ReadByte()); //not sure about my bit operations also order :zzz: CHECK IT!
}public int Read( ushort[] buffer, int offset, int length)
{
Position += offset;
int i = 0;
if (CanRead) {
for (; i < length; i++)
{
buffer[i] = ReadUShort();
}
}
return i;
}You can try that, someone might have an easier idea :~ Hope this helps :) Give them a chance! Do it for the kittens, dear God, the kittens! As seen on MS File Transfer: Please enter an integer between 1 and 2.