重要改变：修复一次运行全部测试时，卡死失败的错误,并大大缩短测试时间（分钟到秒）

原因猜测：每个测试，获取一个新连接，导致TCP/IP连接数过大，出现Redis超时。
解决：获取IConnectionMultiplexer，使用单例方法，多扣位共享一个连接。

RedisStudyTest/RedisHelperTest.cs

@@ -17,11 +17,6 @@ namespace RedisStudyTest
 {
     public class RedisHelperTest
     {
-       [Fact]
-        public void MyTest()
-        {
-            Assert.True(1 < 99);
-        }
 
         [Fact]
         public void GetRedisDatabaseTest()
@@ -36,18 +31,9 @@ namespace RedisStudyTest
         [Fact]
         public void GetRedisDatabaseTest2()
         {
-            //ConfigurationOptions options = new ConfigurationOptions();
+            var db = RedisHelper.GetConnectionMultiplexer();
-            //options.DefaultDatabase = 1;
+            var db2 = RedisHelper.GetConnectionMultiplexer();
-            //options.EndPoints.Add("127.0.0.1", 6379);
+            Assert.Equal(db, db2);
-
-            //IConnectionMultiplexer connection = ConnectionMultiplexer.Connect(options);
-
-            //var mock = new Mock<IConnectionMultiplexer>(options);
-            ////mock.Setup(a => a.GetDatabase(1)).Returns(IDatabase);
-
-
-            //var myDB = mock.Object;
-            ////Assert.Equal("127.0.0.1", myDB.Multiplexer.Configuration);
         }
 
         [Fact]

RedisStuy/RedisHelper.cs

@@ -13,24 +13,37 @@ namespace RedisStuy
     /// <summary>
     /// 客户端操作
     /// </summary>
-    public static class RedisHelper
+    public sealed class RedisHelper
     {
-        /// <summary>
+
-        /// 获取 Redis连接
+        private static readonly IConnectionMultiplexer connectionMultiplexer = IniConnection();
-        /// (此为共享和线程安全的，可以设计成单例模式)
+
-        /// </summary>
+        private static IConnectionMultiplexer IniConnection()
-        public static IConnectionMultiplexer GetConnectionMultiplexer()
         {
             ConfigurationOptions options = new ConfigurationOptions();
+            options.KeepAlive = 200;
             options.DefaultDatabase = 1;
             options.AllowAdmin = true;
             options.EndPoints.Add("127.0.0.1", 6379);
 
             IConnectionMultiplexer connection = ConnectionMultiplexer.Connect(options);
-
             return connection;
         }
 
+        private RedisHelper()
+        {
+
+        }
+
+        /// <summary>
+        /// 获取 Redis连接
+        /// (此为共享和线程安全的，可以设计成单例模式)
+        /// </summary>
+        public static IConnectionMultiplexer GetConnectionMultiplexer()
+        {
+            return connectionMultiplexer;
+        }
+
 
         /// <summary>
         /// 获取 默认Reids服务器