From 81637c01c40f1390b7ad3df48cd3b79840d1eabf Mon Sep 17 00:00:00 2001
From: liuchao <liuchao@nbdeli.com>
Date: Fri, 30 Sep 2022 13:39:58 +0800
Subject: [PATCH] =?UTF-8?q?=E5=AD=90=E6=A0=91=E5=B9=B3=E9=93=BA=E6=9F=A5?=
 =?UTF-8?q?=E8=AF=A2ToChildList()/ToChildListAsync()=E6=80=A7=E8=83=BD?=
 =?UTF-8?q?=E4=BC=98=E5=8C=96?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../QueryableProvider/QueryableProvider.cs    | 54 ++++++++++---------
 .../QueryableProvider/QueryableProvider.cs    | 54 ++++++++++---------
 2 files changed, 58 insertions(+), 50 deletions(-)

diff --git a/Src/Asp.Net/SqlSugar/Abstract/QueryableProvider/QueryableProvider.cs b/Src/Asp.Net/SqlSugar/Abstract/QueryableProvider/QueryableProvider.cs
index db49b983d..d8799ef19 100644
--- a/Src/Asp.Net/SqlSugar/Abstract/QueryableProvider/QueryableProvider.cs
+++ b/Src/Asp.Net/SqlSugar/Abstract/QueryableProvider/QueryableProvider.cs
@@ -2418,33 +2418,37 @@ namespace SqlSugar
                 exp = (exp as UnaryExpression).Operand;
             }
             var parentIdName = (exp as MemberExpression).Member.Name;
-            List<T> result = list.Where(it =>
-            {
-                var parentValue = it.GetType().GetProperty(parentIdName).GetValue(it);
-                return  parentValue.ObjToString() == rootValue.ObjToString();
-
-            }).ToList();
-            if (result != null && result.Count > 0)
-            {
-                List<T> childList = new List<T>();
-                foreach (var item in result)
-                {
-                    var pkValue = item.GetType().GetProperty(pkName).GetValue(item);
-                    childList.AddRange(GetChildList(parentIdExpression, pkName, list, pkValue,false));
-                }
-                result.AddRange(childList);
-            }
-            if (isRoot)
-            {
-                result.AddRange(list.Where(it =>
-                {
-                    var pkValue = it.GetType().GetProperty(pkName).GetValue(it);
-                    return pkValue.ObjToString() == rootValue.ObjToString();
-
-                }).ToList());
-            }
+            var result = BuildChildList(list, pkName, parentIdName, rootValue);
             return result;
         }
+
+        private static List<T> BuildChildList(List<T> list, string idName, string pIdName, object rootValue)
+        {
+            var type = typeof(T);
+            var idProp = type.GetProperty(idName);
+            var pIdProp = type.GetProperty(pIdName);
+
+            var kvpList = list.ToDictionary(x => x, v => idProp.GetValue(v).ObjToString());
+            var groupKv = list.GroupBy(x => pIdProp.GetValue(x).ObjToString()).ToDictionary(k => k.Key, v => v.ToList());
+
+            Func<string, List<T>> fc = null;
+            fc = (rootVal) =>
+            {
+                var finalList = new List<T>();
+                if (groupKv.TryGetValue(rootVal, out var nextChildList))
+                {
+                    finalList.AddRange(nextChildList);
+                    foreach (var child in nextChildList)
+                    {
+                        finalList.AddRange(fc(kvpList[child]));
+                    }
+                }
+                return finalList;
+            };
+
+            return fc(rootValue.ObjToString());
+        }
+
         private List<T> GetTreeRoot(Expression<Func<T, IEnumerable<object>>> childListExpression, Expression<Func<T, object>> parentIdExpression, string pk, List<T> list,object rootValue)
         {
             var childName = ((childListExpression as LambdaExpression).Body as MemberExpression).Member.Name;
diff --git a/Src/Asp.NetCore2/SqlSugar/Abstract/QueryableProvider/QueryableProvider.cs b/Src/Asp.NetCore2/SqlSugar/Abstract/QueryableProvider/QueryableProvider.cs
index db49b983d..12ed9879f 100644
--- a/Src/Asp.NetCore2/SqlSugar/Abstract/QueryableProvider/QueryableProvider.cs
+++ b/Src/Asp.NetCore2/SqlSugar/Abstract/QueryableProvider/QueryableProvider.cs
@@ -2418,33 +2418,37 @@ namespace SqlSugar
                 exp = (exp as UnaryExpression).Operand;
             }
             var parentIdName = (exp as MemberExpression).Member.Name;
-            List<T> result = list.Where(it =>
-            {
-                var parentValue = it.GetType().GetProperty(parentIdName).GetValue(it);
-                return  parentValue.ObjToString() == rootValue.ObjToString();
-
-            }).ToList();
-            if (result != null && result.Count > 0)
-            {
-                List<T> childList = new List<T>();
-                foreach (var item in result)
-                {
-                    var pkValue = item.GetType().GetProperty(pkName).GetValue(item);
-                    childList.AddRange(GetChildList(parentIdExpression, pkName, list, pkValue,false));
-                }
-                result.AddRange(childList);
-            }
-            if (isRoot)
-            {
-                result.AddRange(list.Where(it =>
-                {
-                    var pkValue = it.GetType().GetProperty(pkName).GetValue(it);
-                    return pkValue.ObjToString() == rootValue.ObjToString();
-
-                }).ToList());
-            }
+            var result = BuildChildList(list, pkName, parentIdName, rootValue);
             return result;
         }
+
+        private static List<T> BuildChildList(List<T> list, string idName, string pIdName, object rootValue)
+        {
+            var type = typeof(T);
+            var idProp = type.GetProperty(idName);
+            var pIdProp = type.GetProperty(pIdName);
+
+            var kvpList = list.ToDictionary(x => x, v => idProp.GetValue(v).ObjToString());
+            var groupKv = list.GroupBy(x => pIdProp.GetValue(x).ObjToString()).ToDictionary(k => k.Key, v => v.ToList());
+
+            Func<string, List<T>> fc = null;
+            fc = (rootValue) =>
+            {
+                var finalList = new List<T>();
+                if (groupKv.TryGetValue(rootValue, out var nextChildList))
+                {
+                    finalList.AddRange(nextChildList);
+                    foreach (var child in nextChildList)
+                    {
+                        finalList.AddRange(fc(kvpList[child]));
+                    }
+                }
+                return finalList;
+            };
+
+            return fc(rootValue.ObjToString());
+        }
+
         private List<T> GetTreeRoot(Expression<Func<T, IEnumerable<object>>> childListExpression, Expression<Func<T, object>> parentIdExpression, string pk, List<T> list,object rootValue)
         {
             var childName = ((childListExpression as LambdaExpression).Body as MemberExpression).Member.Name;