Casting char/byte array to IntPtr and convert char array to byte array

Question

Hi,

1 - What is the fast way to copy/cast array of chars to array of bytes (not using loop) ?

byte[] ByteArray <<<==== char[] ByteArray1

 

2- is it posible to cast array of chars / array of bytes to IntPtr ?

IntPtr pointer = (?????) ByteArray  ;

 

Best Regards,

Joe

Answer 1

You can't cast a byte array to a char array and vice versa because a char is 16-bits and a byte is 8-bits.

Answer 2

As I know char is 8 bit , 0x00 to 0xFF !!!!!

 

Answer 3

char in C# is 16-bits, not 8-bits.  Char is Unicode in .NET.

 

Answer 4

I can't imaging that there are no function that I can use to use the pointer ? the data is residint in the memmory as ablock of bytes, I should have the ability to use those data in any way I want I can use them as char or as just number . so It should be a way to get the pointer from char array make it byte array :

 

char [] aray = {.......................}

byte [] arrayByte

 

arrayByte = &array  or (byte*)(void*)array :-(

from this poit I can use arrayByte.Length -> this can be aray.Length*2

 

 

 

Answer 5

You could use Marshal.UnsafeAddrOfPinnedArrayElement(array, 0) to get a memory pointer to the array.  You can do what ever you want from that pointer if you want.

 

Answer 6

Thanks a lot, you help me .

 

 

//Unmanage code send me an array of unsigned char represent RowData

 

void  DrawImage(char [] arrayOfCharsFromUnmanageCode)

{

 

byte[] bmpByteArray = new byte[width*height];

 

 

IntPtr pSource =System.Runtime.InteropServices.Marshal.UnsafeAddrOfPinnedArrayElement(arrayOfCharsFromUnmanageCode, 0);

System.Runtime.InteropServices.Marshal.Copy(pSource,bmpByteArray,0,Math.Min(arrayOfCharsFromUnmanageCode.Length,bmpByteArray.Length));

......

}

Answer 7

I still have my original Kerningham and Ritchie Programming in C book.  Life was much simpler then...
I loved programming in C because it gave me such flexibility and I was able to get close to the memory...
Now I have to bend over backwards in order to set bytes in a message and to cast them to ints, etc.

Is there anything written about bit/byte manipulation in C#?
Thanks!
Mechi

---

Mechi

Answer 8

Joe,

What you want is called marshalling.
Please read the following article:
http://blog.rednael.com/2008/08/29/MarshallingUsingNativeDLLsInNET.aspx

It's an in depth article about marshalling between native code and managed code. It shows which types are interoperable, how to import a DLL, how to pass strings, how to pass structures and how to de-reference pointers.

Basically all the information you need.