LockableList

LockableList<Key, Value> wraps a list into lockable list.

List<string> list = new List<string>();
LockableList<string> lockableList = new LockableList<string>(list);

LockableList.Create(elementType, internalList) creates a list for element type argument.

List<string> list = new List<string>();
var locakableList = LockableList.Create(typeof(string), list);

LockableList.Create(elementType) creates a list for element type with default internal list.

IList list = LockableList.Create(typeof(String));

If internal list is not provided in constuctor, a default list is created.

// Create list
var list = new LockableList<string> { "Value1", "Value2" };

.SetReadOnly() extension method of IReadOnly locks list.

list.SetReadOnly();

After locking write operation throws InvalidOperationException.

try
{
    list.Add("Value3");
}
catch (InvalidOperationException)
{
}

If internal list is not internally synchronized, then it must be externally locked with its .SyncRoot in concurrent use.

// Create non-internally synchronized list
var list = new LockableList<int>();
// Is underlying map internally synchronized
WriteLine(list.IsSynchronized); // False
// Add concurrently
Parallel.For(0, 10, (int i) => { lock (list.SyncRoot) list.Add(i); });
// Lock
list.SetReadOnly();
// Print values
WriteLine(string.Join(',', list)); // 8,7,5,0,4,6,9,1,3,2

When internal list is internally synchronized, then values can be added concurrently without lock.

// Create internal list (internally synchronized)
var internalList = new ArrayList<int>();
// Create wrapper
var list = new LockableList<int>(internalList);
// Is underlying map internally synchronized
WriteLine(list.IsSynchronized); // True
// Add concurrently
Parallel.For(0, 10, (int i) => list.Add(i));
// Lock
list.SetReadOnly();
// Print values
WriteLine(string.Join(',', list)); // 0,1,4,5,3,7,8,2,6,9

Full Example

Full example

using System;
using System.Collections;
using System.Collections.Generic;
using System.Threading.Tasks;
using Avalanche.Utilities;
using static System.Console;

public class lockablelist
{
    public static void Run()
    {
        {
            // <01>
            List<string> list = new List<string>();
            LockableList<string> lockableList = new LockableList<string>(list);
            // </01>
        }
        {
            // <02>
            List<string> list = new List<string>();
            var locakableList = LockableList.Create(typeof(string), list);
            // </02>
        }
        {
            // <03>
            IList list = LockableList.Create(typeof(String));
            // </03>
        }
        {
            // <04>
            // Create list
            var list = new LockableList<string> { "Value1", "Value2" };
            // </04>
            // <05>
            list.SetReadOnly();
            // </05>
            // <06>
            try
            {
                list.Add("Value3");
            }
            catch (InvalidOperationException)
            {
            }
            // </06>
        }
        {
            // <11>
            // Create non-internally synchronized list
            var list = new LockableList<int>();
            // Is underlying map internally synchronized
            WriteLine(list.IsSynchronized); // False
            // Add concurrently
            Parallel.For(0, 10, (int i) => { lock (list.SyncRoot) list.Add(i); });
            // Lock
            list.SetReadOnly();
            // Print values
            WriteLine(string.Join(',', list)); // 8,7,5,0,4,6,9,1,3,2
            // </11>
        }
        {
            // <12>
            // Create internal list (internally synchronized)
            var internalList = new ArrayList<int>();
            // Create wrapper
            var list = new LockableList<int>(internalList);
            // Is underlying map internally synchronized
            WriteLine(list.IsSynchronized); // True
            // Add concurrently
            Parallel.For(0, 10, (int i) => list.Add(i));
            // Lock
            list.SetReadOnly();
            // Print values
            WriteLine(string.Join(',', list)); // 0,1,4,5,3,7,8,2,6,9
            // </12>
        }
    }
}