public class Test
{
    public void Get()
    {
        lock (this)  // 鎖定當(dāng)前實(shí)例
        {
            //執(zhí)行代碼
        }
    }
}

// demo
internal class Program
{
    static void Main(string[] args)
    {
        TestDemo testDemo = new TestDemo();
        //開(kāi)啟新線程，不然單線程執(zhí)行，沒(méi)有并發(fā)，加鎖也沒(méi)有意義
        Task.Run(() =>
        {
            testDemo.Get();
        });
        Thread.Sleep(2000); //等待2秒，可以讓新線程先加鎖
        testDemo.Set();
        Console.ReadLine();
    }
}
public class TestDemo
{
    public void Get(int index)
    {
        lock (this)
        {
            Thread.Sleep(5000);
            Console.WriteLine("執(zhí)行完成，{index}");
        }
    }
    public void Set()
    {
        lock (this) //顯式加鎖，不然還是可以并發(fā)執(zhí)行
        {
            Console.WriteLine("Set完成");
        }
    }
}

public class Test
{
    private readonly object _lockObject = new object();  // 私有鎖對(duì)象
    public void Get()
    {
        lock (_lockObject)  // 鎖住私有對(duì)象
        {
            //執(zhí)行代碼
        }
    }
}

internal class Program
{
    static void Main(string[] args)
    {
        TestDemo testDemo = new TestDemo();
        Task.Run(() =>
        {
            testDemo.Get();
        });
        Thread.Sleep(2000);
        testDemo.Set();
        Console.ReadLine();
    }
}
public class TestDemo
{
    private readonly object _lockObject = new object();
    public void Get()
    {
        lock (_lockObject)
        {
            Thread.Sleep(5000);
            Console.WriteLine("Get執(zhí)行完成");
        }
    }
    public void Set()
    {
        lock (_lockObject)
        {
            Console.WriteLine("Set執(zhí)行完成");
        }
    }
}
 

public class Test
{
    private static readonly object _lockObject = new object();  // 靜態(tài)鎖對(duì)象
    public void Get()
    {
        lock (_lockObject)  // 鎖住靜態(tài)鎖對(duì)象
        {
            //執(zhí)行代碼
        }
    }
}

internal class Program
{
    static void Main(string[] args)
    {
        //開(kāi)啟十個(gè)線程，并行執(zhí)行Get方法
        Parallel.For(0, 10, i =>
        {
            new TestDemo().Get();
        });
        Console.ReadLine();
    }
}
public class TestDemo
{
    private static int _count = 0;
    private static readonly object _lockObject = new object();
    public void Get()
    {
        lock (_lockObject)
        {
            _count += 1;
            Thread.Sleep(2000); //線程延遲，模擬處理數(shù)據(jù)
            Console.WriteLine($@"當(dāng)前值：{_count}");
        }
    }
}

public class Test
{
    //私有靜態(tài)對(duì)象
    private static object lockObj = new object();
    public void Get()
    {
        Monitor.Enter(lockObj); //獲取鎖
        try
        {
            //具體執(zhí)行邏輯
        }
        catch (Exception ex)
        {
        }
        finally
        {
            Monitor.Exit(lockObj); // 釋放信號(hào)量
        }
    }
}

static async Task Main(string[] args)
{
    Task.Run(() =>
    {
        new TestDemo().Get();
    });
    Task.Run(() =>
    {
        new TestDemo().Set();
    });
    Console.ReadLine();
}
public class TestDemo
{
    private static object lockObj = new object();
    public void Get()
    {
        Monitor.Enter(lockObj);
        try
        {
            Console.WriteLine($"Get方法開(kāi)始執(zhí)行");
            //釋放當(dāng)前鎖，讓其他等待線程執(zhí)行
            Monitor.Wait(lockObj, 1000);
            Console.WriteLine($"Get方法執(zhí)行完畢");
        }
        catch (Exception ex)
        {
        }
        finally
        {
            // 確保鎖被釋放
            Monitor.Exit(lockObj);
        }
    }
    public void Set()
    {
        Monitor.Enter(lockObj);
        try
        {
            Console.WriteLine($"Set方法開(kāi)始執(zhí)行");
            Thread.Sleep(1000);
            Console.WriteLine($"Set方法執(zhí)行完畢");
            //喚醒等待的線程
            Monitor.Pulse(lockObj);
        }
        catch (Exception ex)
        {
        }
        finally
        {
            // 確保鎖被釋放
            Monitor.Exit(lockObj);
        }
    }
}

public class Test
{
    //靜態(tài)信號(hào)鎖，同時(shí)可以3個(gè)線程同時(shí)訪問(wèn)
    private static readonly SemaphoreSlim semaphore = new SemaphoreSlim(3);
    public void Get()
    {
        semaphore.Wait(); //獲取鎖
        try
        {
            //具體執(zhí)行邏輯
        }
        catch (Exception ex)
        {
        }
        finally
        {
            semaphore.Release(); // 釋放信號(hào)量
        }
    }
}

public class TestDemo
{
    // 使用 SemaphoreSlim + ConcurrentDictionary 來(lái)保護(hù)共享資源
    private static readonly ConcurrentDictionary<string, SemaphoreSlim> _locks = new ConcurrentDictionary<string, SemaphoreSlim>();
    //獲取鎖
    private static SemaphoreSlim GetLock(string key)
    {
        return _locks.GetOrAdd(key, new SemaphoreSlim(1, 1));
    }
    public async Task Get(string key)
    {
        var semaphore = GetLock(key);
        var lockAcquired = false;
        try
        {
            lockAcquired = semaphore.Wait(0); // 嘗試立即獲取信號(hào)量
            if (!lockAcquired) return; //獲取鎖失敗，返回，不會(huì)等待上一個(gè)加鎖的線程釋放
            //獲取鎖成功，執(zhí)行以下邏輯
        }
        catch (Exception ex)
        {
        }
        finally
        {
            if (lockAcquired)
            {
                // 釋放鎖
                semaphore.Release();
                // 移除鎖(防止內(nèi)存泄漏)
                _locks.TryRemove(key, out _);
            }
        }
    }
}

public class Test
{
    //創(chuàng)建一個(gè) Mutex鎖
    private static Mutex mutex = new Mutex();
    public void Get()
    {
        //獲取 Mutex鎖
        mutex.WaitOne();
        try
        {
            //具體執(zhí)行邏輯
        }
        catch (Exception ex)
        {
        }
        finally
        {
            //釋放 Mutex鎖
            mutex.ReleaseMutex();
        }
    }
}

internal class Program
{
    static void Main(string[] args)
    {
        new TestDemo().Get();
        Console.WriteLine("全部執(zhí)行完畢");
        Console.ReadLine();
    }
}
public class TestDemo
{
    Mutex mutex = new Mutex(false, "Global\\MutexTest");
    public void Get()
    {
        mutex.WaitOne();
        try
        {
            Thread.Sleep(30000);
            Console.WriteLine($"Get執(zhí)行完成");
        }
        catch (Exception ex)
        {
        }
        finally
        {
            mutex.ReleaseMutex();
        }
    }
}

public class Test
{
    //創(chuàng)建一個(gè) ReaderWriterLockSlim 鎖
    private static readonly ReaderWriterLockSlim lockSlim = new ReaderWriterLockSlim();
    public void Get()
    {
        //獲取 讀鎖
        lockSlim.EnterReadLock();
        //獲取 寫鎖
        lockSlim.EnterWriteLock();
        try
        {
            //具體執(zhí)行邏輯
        }
        catch (Exception ex)
        {
        }
        finally
        {
            //釋放鎖
            lockSlim.ExitReadLock();
            lockSlim.ExitWriteLock();
        }
    }
}

internal class Program
{
    static void Main(string[] args)
    {
        Task.Run(() =>
        {
            new TestDemo().WriteData();
        });
        Thread.Sleep(1000);
        Task.Run(() => {
            new TestDemo().ReadData();
        });
        Console.WriteLine("全部執(zhí)行完畢");
        Console.ReadLine();
    }
}
public class TestDemo
{
    private static readonly ReaderWriterLockSlim lockSlim = new ReaderWriterLockSlim();
    public void ReadData()
    {
        lockSlim.EnterReadLock();
        try
        {
            Console.WriteLine("開(kāi)始執(zhí)行讀鎖");
            Thread.Sleep(1000);
            Console.WriteLine("執(zhí)行讀鎖結(jié)束");
        }
        catch (Exception)
        {
        }
        finally
        {
            lockSlim.ExitReadLock();
        }
    }
    public void WriteData()
    {
        //是一個(gè)可升級(jí)的讀鎖
        lockSlim.EnterUpgradeableReadLock();
        try
        {
            try
            {
                Console.WriteLine("開(kāi)始執(zhí)行寫鎖");
                //升級(jí)為寫鎖
                lockSlim.EnterWriteLock();
                Thread.Sleep(10000);
                Console.WriteLine("寫鎖執(zhí)行完畢");
            }
            catch (Exception)
            {
            }
            finally
            {
                lockSlim.ExitWriteLock();
            }
        }
        catch (Exception)
        {
        }
        finally
        {
            lockSlim.EnterUpgradeableReadLock();
        }
    }
}

static async Task Main(string[] args)
{
    Parallel.For(0, 50, async i =>
    {
        // 連接 Redis
        var redis = ConnectionMultiplexer.Connect("localhost");
        // 創(chuàng)建鎖管理對(duì)象
        var distributedLock = new RedisDistributedLock(redis);
        // 鎖標(biāo)識(shí)和唯一值
        string lockKey = "CustomerRedisLock";
        string lockValue = Guid.NewGuid().ToString();
        TimeSpan lockTimeout = TimeSpan.FromSeconds(10);
        // 嘗試獲取鎖
        bool isLockAcquired = await distributedLock.AcquireLockAsync(lockKey, lockValue, lockTimeout);
        if (isLockAcquired)
        {
            Console.WriteLine("鎖已獲取，執(zhí)行任務(wù)中...");
            try
            {
                // 模擬任務(wù)執(zhí)行
                await Task.Delay(2000);
            }
            finally
            {
                // 釋放鎖
                bool isLockReleased = await distributedLock.ReleaseLockAsync(lockKey, lockValue);
                Console.WriteLine(isLockReleased ? "鎖已釋放" : "釋放鎖失敗或鎖已過(guò)期");
            }
        }
        else
        {
            Console.WriteLine("未能獲取鎖");
        }
    });
    Console.ReadLine();
}
public class RedisDistributedLock
{
    private readonly IDatabase _redisDatabase;
    private readonly TimeSpan _defaultLockTimeout = TimeSpan.FromSeconds(10); // 默認(rèn)鎖超時(shí)時(shí)間
    public RedisDistributedLock(IConnectionMultiplexer redisConnection)
    {
        _redisDatabase = redisConnection.GetDatabase();
    }
    //獲取鎖
    public async Task<bool> AcquireLockAsync(string key, string value, TimeSpan? timeout = null)
    {
        var lockTimeout = timeout ?? _defaultLockTimeout;
        return await _redisDatabase.StringSetAsync(key, value, lockTimeout, When.NotExists);
    }
    //釋放鎖
    public async Task<bool> ReleaseLockAsync(string key, string value)
    {
        // 獲取當(dāng)前鎖的值
        var currentValue = await _redisDatabase.StringGetAsync(key);
        // 如果當(dāng)前鎖的值和傳入的值相等，則釋放鎖
        if (currentValue == value)
        {
            return await _redisDatabase.KeyDeleteAsync(key);
        }
        return false; // 鎖值不匹配，表示鎖已經(jīng)被其他客戶端持有
    }
}