Unmanaged Array

An Effective tool for unmanaged array in C#.

About

Array in C# is allocated in managed memory.

UnmanagedArray<T> in this library is allocated in unmanaged memory.

In other words, items in UnmanagedArray<T> is not collected by Garbage Collection.

Supported Types

The only type of item UnmanagedArray<T> supports is unmanaged type.

unmanaged type is int, float, recursive-unmanaged struct, and so on.

string, and other types which are class are NOT SUPPORTED.

(because reference types are allocated in managed memory on C#.)

Building from Source

$ git clone https://github.com/ikorin24/UnmanagedArray.git
$ cd UnmanagedArray
$ dotnet build src/UnmanagedArray/UnmanagedArray.csproj -c Release

Installation

Install from Nuget by package manager console (in Visual Studio).

https://www.nuget.org/packages/UnmanagedArray

PM> Install-Package UnmanagedArray

How to Use

The way of use is similar to normal array.

Unmanaged resources are release when an instance goes through the scope.

using UnmanageUtility;

// UnmanagedArray releases its memories when it goes through the scope.
using(var array = new UnmanagedArray<int>(10))
{
    for(int i = 0;i < array.Length;i++)
    {
        array[i] = i;
    }
}

If not use the using scope, you can release the memories by Dispose() method.

var array = new UnmanagedArray<int>(10);
array[3] = 100;
array.Dispose();       // The memories allocated in unmanaged is released here.

Of cource, LINQ is supported.

using(var array = Enumerable.Range(0, 10).ToUnmanagedArray())
using(var array2 = array.Where(x => x >= 5).ToUnmanagedArray()) {
    for(int i = 0; i < array2.Length; i++) {
        Console.WriteLine(array2[i]);       // 5, 6, 7, 8, 9
    }
}

NOTICE

UnmanagedArray<T> has Finalizer and releases its unmanaged resources automatically when you forget releasing that.

However, you have to release them explicitly ( by using scope or Dispose() ).

New Feature of ver 2.1.0

UnmanagedList<T> is available, which the way of use is similar to List<T>.

using(var list = new UnmanagedList<int>())
{
    list.Add(4);
    list.Add(9);
    foreach(var num in list)
    {
        Console.WriteLine(num);
    }
}

License and Credits

This is under MIT license.

This software includes the work that is distributed in the Apache License 2.0.

Apache License 2.0 (http://www.apache.org/licenses/LICENSE-2.0)

Author

github: ikorin24

Release Note

2020/01/11 v1.0.0

• First release

2020/01/12 v1.0.1

• Performance improvement of iteration by foreach, that is as faster as T[] (normal array).

2020/01/15 v1.0.2

• Great performance improvement of accessing to the item by index. (array[i])

2020/04/30 v1.0.3

• Performance improvement.
• Add GC.AddMemoryPressure in constructor and GC.RemoveMemoryPressure in destructor.

2020/04/30 v2.0.0

• Change namespace into UnmanageUtility.

2020/06/07 v2.0.1

2020/07/27 v2.1.0-rc

• Add UnmanagedList<T>.

2020/10/05 v2.1.0

• Performance improvement.
• Add some methods.

2020/11/26 v2.1.1

• Add UnmanagedArray<T>.Empty static property.
• Add property setter of UnmanagedList<T>.Capacity.

2021/01/05 v2.1.2

• Add UnmanagedArray<T>.AsSpan overload methods.
• Package for multi target frameworks. (net48, netcoreapp3.1, net5.0, netstandard2.0, netstandard2.1)
• Fix small bugs.

2021/02/10 v2.1.3

• Add UnmanagedList<T>.Extend method.