C#•3y ago

Convert int[] to byte[]?

Could anyone help me convert an array of integers to an array of bytes?

12 Replies

sibber•3y ago

Reads bytes as primitives with specific endianness.

WAASULOP•3y ago

Would this be a good idea?

byte[] bytes = intArray.SelectMany(BitConverter.GetBytes).ToArray()

byte[] bytes = intArray.SelectMany(BitConverter.GetBytes).ToArray()

that doesnt make sense, since byte's maximum value is 255 what if an integer is 512 ? you probably want a 2d array

sibber•3y ago

i assume they want to convert each int to an array of bytes

byte[][] bytes = intArray.Select(x => BitConverter.GetBytes(x)).ToArray();

byte[][] bytes = intArray.Select(x => BitConverter.GetBytes(x)).ToArray();

ero•3y ago

what they had originally makes perfect sense and works fine absolutely no reason to correct that unless they want a faster version

id allocate once and for it more efficient than linq

MODiX•3y ago

Ero#1111

REPL Result: Success

using System.Runtime.InteropServices;

int[] foo = { 1, 2, 3, 4, 5 };
byte[] bar = MemoryMarshal.AsBytes<int>(foo).ToArray();

bar

using System.Runtime.InteropServices;

int[] foo = { 1, 2, 3, 4, 5 };
byte[] bar = MemoryMarshal.AsBytes<int>(foo).ToArray();

bar

Result: byte[]

AQAAAAIAAAADAAAABAAAAAUAAAA=

AQAAAAIAAAADAAAABAAAAAUAAAA=

Compile: 565.667ms | Execution: 44.727ms | React with ❌ to remove this embed.

ero•3y ago

ah, right modix turns bytes into chars

MODiX•3y ago

Cyberrex#8052

REPL Result: Success

using System.Runtime.InteropServices;

int[] foo = { 1, 2, 3, 4, 5 };
byte[] bar = MemoryMarshal.AsBytes<int>(foo).ToArray();

string.Join("", bar)

using System.Runtime.InteropServices;

int[] foo = { 1, 2, 3, 4, 5 };
byte[] bar = MemoryMarshal.AsBytes<int>(foo).ToArray();

string.Join("", bar)

Result: string

10002000300040005000

10002000300040005000

Compile: 621.330ms | Execution: 50.969ms | React with ❌ to remove this embed.

mtreit•3y ago

I think I would use MemoryMarshal.Cast for this.

Span<byte> bytes = MemoryMarshal.Cast<int, byte>(foo);

Span<byte> bytes = MemoryMarshal.Cast<int, byte>(foo);

ah that slipped my mind, did not think thats what they meant even tho i used those kinds of things in a project im working on