- 增加DynamicEntity立nuget包

Extensions/FreeSql.Extensions.DynamicEntity/DynamicCompileHelper.cs

@@ -0,0 +1,74 @@
+using System;
+using System.Collections.Concurrent;
+using System.Collections.Generic;
+using System.Linq.Expressions;
+
+namespace FreeSql.Extensions.DynamicEntity
+{
+    /// <summary>
+    /// 动态创建对象帮助类
+    /// </summary>
+    public class DynamicCompileHelper
+    {
+        /// <summary>
+        /// 动态构建Class - Type
+        /// </summary>
+        /// <returns></returns>
+        public static DynamicCompileBuilder DynamicBuilder()
+        {
+            return new DynamicCompileBuilder();
+        }
+
+        /// <summary>
+        /// 委托缓存
+        /// </summary>
+        private static readonly ConcurrentDictionary<string, Delegate>
+            DelegateCache = new ConcurrentDictionary<string, Delegate>();
+
+        /// <summary>
+        /// 设置动态对象的属性值
+        /// </summary>
+        /// <param name="type"></param>
+        /// <param name="porpertys"></param>
+        /// <returns></returns>
+        public static object CreateObjectByType(Type type, Dictionary<string, object> porpertys)
+        {
+            if (type == null)
+                return null;
+            object istance = Activator.CreateInstance(type);
+            if (istance == null)
+                return null;
+            //根据key确定缓存
+            var cacheKey = $"{type.GetHashCode()}{porpertys.GetHashCode()}";
+            var dynamicDelegate = DelegateCache.GetOrAdd(cacheKey, key =>
+            {
+                //表达式目录树构建委托
+                var typeParam = Expression.Parameter(type);
+                var dicParamType = typeof(Dictionary<string, object>);
+                var dicParam = Expression.Parameter(dicParamType);
+                var exps = new List<Expression>();
+                var tempRef = Expression.Variable(typeof(object));
+                foreach (var pinfo in porpertys)
+                {
+                    var propertyInfo = type.GetProperty(pinfo.Key);
+                    if (propertyInfo == null)
+                        continue;
+                    var propertyName = Expression.Constant(pinfo.Key, typeof(string));
+                    exps.Add(Expression.Call(dicParam, dicParamType.GetMethod("TryGetValue"), propertyName, tempRef));
+                    exps.Add(Expression.Assign(Expression.MakeMemberAccess(typeParam, propertyInfo),
+                        Expression.Convert(tempRef, propertyInfo.PropertyType)));
+                    exps.Add(Expression.Assign(tempRef, Expression.Default(typeof(object))));
+                }
+
+                var returnTarget = Expression.Label(type);
+                exps.Add(Expression.Return(returnTarget, typeParam));
+                exps.Add(Expression.Label(returnTarget, Expression.Default(type)));
+                var block = Expression.Block(new[] { tempRef }, exps);
+                var @delegate = Expression.Lambda(block, typeParam, dicParam).Compile();
+                return @delegate;
+            });
+            var dynamicInvoke = dynamicDelegate.DynamicInvoke(istance, porpertys);
+            return dynamicInvoke;
+        }
+    }
+}