Write a NativeArray to a stream without a temporary, managed array

StreamExtension.cs

// Copyright 2021 Andreas Atteneder
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//      http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//


// Unity 2022 LTS and newer provide an implicit cast from NativeArray to ReadOnlySpan, removing the need for this entirely.
#if !UNITY_2022_2_OR_NEWER
using System;
using System.IO;
using Unity.Collections;
using Unity.Collections.LowLevel.Unsafe;
using UnityEngine;

public static class StreamExtension {
    public static unsafe void Write(this Stream stream, NativeArray<byte> array) {
        var span = new ReadOnlySpan<byte>(array.GetUnsafeReadOnlyPtr(), array.Length);
        stream.Write(span);
    }
}
#endif

Use array.AsSpan();

@dw8869 Thanks for pointing this one out!

I've found ways to improve on it still:

1. use array.AsReadOnlySpan()
2. Remove the extension method altogether, since Unity 2022 and newer support implicit cast to ReadOnlySpan like so:

public static implicit operator ReadOnlySpan<T>(in NativeArray<T> source)

Meaning you can just do this:

NativeArray<byte> array;
Stream buffer;
buffer.Write(array);

So if you're using 2022 LTS or newer, skip this Gist. For the rest I'll update it soon.

Thanks