Read,write a file binary

[Patrik Malmström]

How do I read, write a file binary?
I want to open, say, file.exe read it in to the program, then write it out
to file2.exe.
Like file copy, anyone have a code sample?

 

[Henrik Dahl]

Patrick,

File.Copy.

More general: BinaryReader/BinaryWriter.


Best regards,

Henrik Dahl

 

[Patrik Malmström]

I've looked at them, but the exampel, wish I always use aren't very good

 

[Pramod Anchuparayil]

Here ya go,

You will need to clean that up a little bit, but its a works...

-- Read

FileStream fs = new FileStream(@"C:\calc.exe", FileMode.OpenOrCreate,
FileAccess.Read);
byte[] MyData= new byte[fs.Length];
fs.Read(MyData, 0, System.Convert.ToInt32(fs.Length));
fs.Close();

-- Write

FileStream fs1 = new FileStream(@"C:\calc1.exe", FileMode.OpenOrCreate,
FileAccess.Write);
BinaryWriter bw = new BinaryWriter(fs1);
bw.Write(MyData);
bw.Close();
fs1.Close();

 

[Henrik Dahl]

Pramod,

Looks OK, but it could benefit from e.g. the following:

*) Use a BinaryReader for reading.
*) use using instead of instantiate ... Close. In this case disposing object
also work in case an exception should be thrown plus it's much more
declarative by nature.
*) Use (int) instead of System.Convert.ToInt32.

Additionally it may be advantageous to use the BitConverter class.


Best regards,

Henrik Dahl

Here ya go,

You will need to clean that up a little bit, but its a works...

-- Read

FileStream fs = new FileStream(@"C:\calc.exe", FileMode.OpenOrCreate,
FileAccess.Read);
byte[] MyData= new byte[fs.Length];
fs.Read(MyData, 0, System.Convert.ToInt32(fs.Length));
fs.Close();

-- Write

FileStream fs1 = new FileStream(@"C:\calc1.exe", FileMode.OpenOrCreate,
FileAccess.Write);
BinaryWriter bw = new BinaryWriter(fs1);
bw.Write(MyData);
bw.Close();
fs1.Close();

I've looked at them, but the exampel, wish I always use aren't very good
"Henrik Dahl" <[email protected]> skrev i meddelandet
it
out

 

[Jon Skeet]

Looks OK, but it could benefit from e.g. the following:

*) Use a BinaryReader for reading.

What's the benefit there? I believe BinaryReader and BinaryWriter are
really there to make it easier to read and write primitives, not blocks
at a time.

*) use using instead of instantiate ... Close. In this case disposing object
also work in case an exception should be thrown plus it's much more
declarative by nature.
*) Use (int) instead of System.Convert.ToInt32.

Additionally it may be advantageous to use the BitConverter class.

Why?

Actually, I'd write it something like:

using (FileStream input = new FileStream (...))
{
using (FileStream output = new FileStream (...))
{
byte[] buffer = new byte[16384];
int len;
while ( (len=input.Read (buffer, 0, buffer.Length)) > 0)
{
output.Write (buffer, 0, len);
}
}
}

That way you don't need to read the whole lot into memory at a time.

 

[Patrik Malmström]

Thanks everyone!

 

[Henrik Dahl]

What's the benefit there? I believe BinaryReader and BinaryWriter are
really there to make it easier to read and write primitives, not blocks
at a time.

Yes, but often people have some order in their bytes where it's possible to
take advantage of these services.

Why?

Same argument as before plus if the current architecture lets him to do it
at a higher abstration level.

Actually, I'd write it something like:

using (FileStream input = new FileStream (...))
{
using (FileStream output = new FileStream (...))
{
byte[] buffer = new byte[16384];
int len;
while ( (len=input.Read (buffer, 0, buffer.Length)) > 0)
{
output.Write (buffer, 0, len);
}
}
}

That way you don't need to read the whole lot into memory at a time.

I agree in your comment, but if this is the real thing to achieve I would
just use File.Copy. If the point just is to do the copying there's no point
in neither BinaryReader or BitConverter of course.

 

[Henrik Dahl]

Patrik,

Have you installed the .NET framework on the machine where you got this
error message?


Best regards,

Henrik Dahl

I'll tried that code, ´but when I was trying to start calc1.exe, it sayed
that calc1.exe doesn't are a Win32 program, sorrym but I'm no good at C#.

Here ya go,

You will need to clean that up a little bit, but its a works...

-- Read

FileStream fs = new FileStream(@"C:\calc.exe", FileMode.OpenOrCreate,
FileAccess.Read);
byte[] MyData= new byte[fs.Length];
fs.Read(MyData, 0, System.Convert.ToInt32(fs.Length));
fs.Close();

-- Write

FileStream fs1 = new FileStream(@"C:\calc1.exe", FileMode.OpenOrCreate,
FileAccess.Write);
BinaryWriter bw = new BinaryWriter(fs1);
bw.Write(MyData);
bw.Close();
fs1.Close();

I've looked at them, but the exampel, wish I always use aren't very good
"Henrik Dahl" <[email protected]> skrev i meddelandet
Patrick,

File.Copy.

More general: BinaryReader/BinaryWriter.


Best regards,

Henrik Dahl

How do I read, write a file binary?
I want to open, say, file.exe read it in to the program, then

write

it