diff --git a/Src/Asp.Net/SqlServerTest/Demos/G_Mapper.cs b/Src/Asp.Net/SqlServerTest/Demos/G_Mapper.cs
index b0f6ad9cf..fe4bf41f3 100644
--- a/Src/Asp.Net/SqlServerTest/Demos/G_Mapper.cs
+++ b/Src/Asp.Net/SqlServerTest/Demos/G_Mapper.cs
@@ -6,7 +6,7 @@ using System.Text;
 
 namespace OrmTest.Demo
 {
-     public class  Mapper : DemoBase
+    public class Mapper : DemoBase
     {
         public static void Init()
         {
@@ -17,12 +17,37 @@ namespace OrmTest.Demo
                         .Select<ViewModelStudent3>().ToList();
 
 
-            var s12 = db.Queryable<Student, School>((st, sc) => st.SchoolId == sc.Id)
-            .Select<ViewModelStudent3>().Mapper(it=> {
-                it.Name = it.Name==null?"默认值":it.Name;
-                it.CreateTime = DateTime.Now.Date;
-                it.Id = it.Id*1000;
-            }).ToList();
+            var s12 = db.Queryable<Student, School>((st, sc) => st.SchoolId == sc.Id).Select<ViewModelStudent3>()
+
+                .Mapper((it, cache) =>
+                {
+
+                    var allSchools = cache.GetListByPrimaryKeys<School>(i => i.SchoolId);//in（ViewModelStudent3[0].id , ViewModelStudent3[1].id...）
+
+                    //Equal to the following writing.
+                    //var allSchools2= cache.Get(list =>
+                    // {
+                    //     var ids=list.Select(i => it.SchoolId).ToList(); 
+                    //     return db.Queryable<School>().In(ids).ToList();
+                    //});Complex writing metho
+
+
+
+                    it.School = allSchools.FirstOrDefault(i => i.Id == it.SchoolId);//one to one
+
+                    it.Schools = allSchools.Where(i => i.Id == it.SchoolId).ToList();//one to many
+
+                }).ToList();
+
+
+            var s13 = db.Queryable<Student, School>((st, sc) => st.SchoolId == sc.Id).Select<ViewModelStudent3>()
+
+                   .Mapper((it, cache) =>
+                   {
+                       it.Schools = db.Queryable<School>().Where(i => i.Id == it.SchoolId).ToList();
+                   }).ToList();
+
+
         }
     }
 }
diff --git a/Src/Asp.Net/SqlServerTest/Models/ViewModelStudent.cs b/Src/Asp.Net/SqlServerTest/Models/ViewModelStudent.cs
index a97dfd98c..75332c12f 100644
--- a/Src/Asp.Net/SqlServerTest/Models/ViewModelStudent.cs
+++ b/Src/Asp.Net/SqlServerTest/Models/ViewModelStudent.cs
@@ -20,5 +20,7 @@ namespace OrmTest.Models
          public string SchoolName { get; set; }
         public string School_Name { get; set; }
         public string ScId { get; set; }
+        public School School { get; set; }
+        public List<School> Schools { get; set; }
     }
 }
diff --git a/Src/Asp.Net/SqlSugar/Abstract/QueryableProvider/QueryableProvider.cs b/Src/Asp.Net/SqlSugar/Abstract/QueryableProvider/QueryableProvider.cs
index ac832c983..23379cebc 100644
--- a/Src/Asp.Net/SqlSugar/Abstract/QueryableProvider/QueryableProvider.cs
+++ b/Src/Asp.Net/SqlSugar/Abstract/QueryableProvider/QueryableProvider.cs
@@ -23,6 +23,7 @@ namespace SqlSugar
         public MappingTableList OldMappingTableList { get; set; }
         public MappingTableList QueryableMappingTableList { get; set; }
         public Action<T> MapperAction { get; set; }
+        public Action<T, MapperCache<T>> MapperActionWithCache { get; set; }
         public bool IsCache { get; set; }
         public int CacheTime { get; set; }
         public bool IsAs { get; set; }
@@ -75,6 +76,11 @@ namespace SqlSugar
             this.MapperAction = mapperAction;
             return this;
         }
+        public virtual ISugarQueryable<T> Mapper(Action<T, MapperCache<T>> mapperAction)
+        {
+            this.MapperActionWithCache = mapperAction;
+            return this;
+        }
 
         public virtual ISugarQueryable<T> AddParameters(object parameters)
         {
@@ -185,6 +191,14 @@ namespace SqlSugar
                 Where(SqlBuilder.SqlFalse);
                 return this;
             }
+            if (pkValues.Length == 1&& pkValues.First() is IEnumerable) {
+                var newValues =new List<object>();
+                foreach (var item in pkValues.First() as IEnumerable)
+                {
+                    newValues.Add(item);
+                }
+                return In(newValues);
+            }
             var pks = GetPrimaryKeys().Select(it => SqlBuilder.GetTranslationTableName(it)).ToList();
             Check.Exception(pks == null || pks.Count != 1, "Queryable.In(params object[] pkValues): Only one primary key");
             string filed = pks.FirstOrDefault();
@@ -1114,13 +1128,28 @@ namespace SqlSugar
                 {
                     if (typeof(TResult) == typeof(T))
                     {
-                        MapperAction((T)Convert.ChangeType(item, typeof(T)));
+                        this.MapperAction((T)Convert.ChangeType(item, typeof(T)));
                     }
                     else {
                         Check.Exception(true, "{0} and {1} are not a type, Try .select().mapper().ToList", typeof(TResult).FullName,typeof(T).FullName);
                     }
                 }
             }
+            if (this.MapperActionWithCache != null)
+            {
+                if (typeof(TResult) == typeof(T))
+                {
+                    var list = (List<T>)Convert.ChangeType(result, typeof(List<T>));
+                    var mapperCache = new MapperCache<T>(list,this.Context);
+                    foreach (T item in list)
+                    {
+                        this.MapperActionWithCache(item, mapperCache);
+                    }
+                }
+                else {
+                    Check.Exception(true, "{0} and {1} are not a type, Try .select().mapper().ToList", typeof(TResult).FullName, typeof(T).FullName);
+                }
+            }
         }
 
         protected int GetCount()
diff --git a/Src/Asp.Net/SqlSugar/Entities/MapperCache.cs b/Src/Asp.Net/SqlSugar/Entities/MapperCache.cs
new file mode 100644
index 000000000..083a39e8b
--- /dev/null
+++ b/Src/Asp.Net/SqlSugar/Entities/MapperCache.cs
@@ -0,0 +1,141 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+
+namespace SqlSugar
+{
+    public class MapperCache<T>
+    {
+        private Dictionary<string, object> caches = new Dictionary<string, object>();
+        private List<T> _list { get; set; }
+        private SqlSugarClient _context { get; set; }
+        private MapperCache()
+        {
+        }
+        public MapperCache(List<T> list, SqlSugarClient context)
+        {
+            _list = list;
+            _context = context;
+        }
+        public Result Get<Result>(Func<List<T>, Result> action)
+        {
+            string key = "Get" + typeof(Result) + action.GetHashCode().ToString();
+            if (caches.ContainsKey(key))
+            {
+                return (Result)caches[key];
+            }
+            else
+            {
+                var result = action(_list);
+                caches.Add(key, result);
+                return result;
+            }
+        }
+        public List<Result> GetListByPrimaryKeys<Result>(Func<T, double?> action) where Result : class, new()
+        {
+            {
+                string key = "GetListById" + typeof(Result) + action.GetHashCode().ToString();
+                return GetListByPrimaryKeys<Result, double?>(action, key);
+            }
+        }
+        public List<Result> GetListByPrimaryKeys<Result>(Func<T, double> action) where Result : class, new()
+        {
+            {
+                string key = "GetListById" + typeof(Result) + action.GetHashCode().ToString();
+                return GetListByPrimaryKeys<Result, double>(action, key);
+            }
+        }
+        public List<Result> GetListByPrimaryKeys<Result>(Func<T, decimal?> action) where Result : class, new()
+        {
+            {
+                string key = "GetListById" + typeof(Result) + action.GetHashCode().ToString();
+                return GetListByPrimaryKeys<Result, decimal?>(action, key);
+            }
+        }
+        public List<Result> GetListByPrimaryKeys<Result>(Func<T, decimal> action) where Result : class, new()
+        {
+            {
+                string key = "GetListById" + typeof(Result) + action.GetHashCode().ToString();
+                return GetListByPrimaryKeys<Result, decimal>(action, key);
+            }
+        }
+        public List<Result> GetListByPrimaryKeys<Result>(Func<T, int?> action) where Result : class, new()
+        {
+            {
+                string key = "GetListById" + typeof(Result) + action.GetHashCode().ToString();
+                return GetListByPrimaryKeys<Result,int?>(action, key);
+            }
+        }
+        public List<Result> GetListByPrimaryKeys<Result>(Func<T, int> action) where Result : class, new()
+        {
+            {
+                string key = "GetListById" + typeof(Result) + action.GetHashCode().ToString();
+                return GetListByPrimaryKeys<Result, int>(action, key);
+            }
+        }
+        public List<Result> GetListByPrimaryKeys<Result>(Func<T, long?> action) where Result : class, new()
+        {
+            {
+                string key = "GetListById" + typeof(Result) + action.GetHashCode().ToString();
+                return GetListByPrimaryKeys<Result, long?>(action, key);
+            }
+        }
+        public List<Result> GetListByPrimaryKeys<Result>(Func<T, long> action) where Result : class, new()
+        {
+            {
+                string key = "GetListById" + typeof(Result) + action.GetHashCode().ToString();
+                return GetListByPrimaryKeys<Result, long>(action, key);
+            }
+        }
+        public List<Result> GetListByPrimaryKeys<Result>(Func<T, string> action) where Result : class, new()
+        {
+            {
+                string key = "GetListById" + typeof(Result) + action.GetHashCode().ToString();
+                return GetListByPrimaryKeys<Result, string>(action, key);
+            }
+        }
+        public List<Result> GetListByPrimaryKeys<Result>(Func<T, Guid> action) where Result : class, new()
+        {
+            {
+                string key = "GetListById" + typeof(Result) + action.GetHashCode().ToString();
+                return GetListByPrimaryKeys<Result, Guid>(action, key);
+            }
+        }
+        public List<Result> GetListByPrimaryKeys<Result>(Func<T, Guid?> action) where Result : class, new()
+        {
+            {
+                string key = "GetListById" + typeof(Result) + action.GetHashCode().ToString();
+                return GetListByPrimaryKeys<Result, Guid?>(action, key);
+            }
+        }
+        public List<Result> GetListByPrimaryKeys<Result>(Func<T, DateTime> action) where Result : class, new()
+        {
+            {
+                string key = "GetListById" + typeof(Result) + action.GetHashCode().ToString();
+                return GetListByPrimaryKeys<Result, DateTime>(action, key);
+            }
+        }
+        public List<Result> GetListByPrimaryKeys<Result>(Func<T, DateTime?> action) where Result : class, new()
+        {
+            {
+                string key = "GetListById" + typeof(Result) + action.GetHashCode().ToString();
+                return GetListByPrimaryKeys<Result, DateTime?>(action, key);
+            }
+        }
+        private List<Result> GetListByPrimaryKeys<Result,FieldType>(Func<T, FieldType> action, string key) where Result : class, new()
+        {
+            if (caches.ContainsKey(key))
+            {
+                return (List<Result>)caches[key];
+            }
+            else
+            {
+                var ids = _list.Select(action).ToList().Distinct().ToList();
+                var result = _context.Queryable<Result>().In(ids).ToList();
+                caches.Add(key, result);
+                return result;
+            }
+        }
+    }
+}
diff --git a/Src/Asp.Net/SqlSugar/Interface/IQueryable.cs b/Src/Asp.Net/SqlSugar/Interface/IQueryable.cs
index d98d62b4b..bab64f28b 100644
--- a/Src/Asp.Net/SqlSugar/Interface/IQueryable.cs
+++ b/Src/Asp.Net/SqlSugar/Interface/IQueryable.cs
@@ -20,6 +20,7 @@ namespace SqlSugar
         ISugarQueryable<T> With(string withString);
         ISugarQueryable<T> Filter(string FilterName, bool isDisabledGobalFilter = false);
         ISugarQueryable<T> Mapper(Action<T> mapperAction);
+        ISugarQueryable<T> Mapper(Action<T, MapperCache<T>> mapperAction);
         ISugarQueryable<T> AddParameters(object parameters);
         ISugarQueryable<T> AddParameters(SugarParameter[] parameters);
         ISugarQueryable<T> AddParameters(List<SugarParameter> parameters);
diff --git a/Src/Asp.Net/SqlSugar/SqlSugar.csproj b/Src/Asp.Net/SqlSugar/SqlSugar.csproj
index ee6dee0d7..2fc62c5f4 100644
--- a/Src/Asp.Net/SqlSugar/SqlSugar.csproj
+++ b/Src/Asp.Net/SqlSugar/SqlSugar.csproj
@@ -78,6 +78,7 @@
     <Compile Include="Entities\CacheKey.cs" />
     <Compile Include="Entities\ConditionalModel.cs" />
     <Compile Include="Entities\ConnMoreSettings.cs" />
+    <Compile Include="Entities\MapperCache.cs" />
     <Compile Include="Entities\SlaveConnectionConfig.cs" />
     <Compile Include="Enum\ConditionalType.cs" />
     <Compile Include="Enum\DbType.cs" />