重写类型转换

Falcon.SugarApi.Test/ObjectExtendTest.cs

@@ -33,6 +33,14 @@ namespace Falcon.SugarApi.Test
             Assert.IsTrue(t.ica.ItemA == "itema");
             Assert.IsTrue(t.ica.Equals(s.ica));
         }
+
+        [TestMethod]
+        public void ChangeTypeTest() {
+            int s = 1;
+            var t = s.ChangeType(typeof(int));
+            Console.WriteLine(t.GetType().FullName);
+            Assert.IsTrue(t.GetType().Equals(typeof(int)));
+        }
     }
 
     public class SourceClass

Falcon.SugarApi/ObjectExtend.cs

@@ -1,4 +1,5 @@
 using System;
+using System.ComponentModel;
 using System.Diagnostics.CodeAnalysis;
 using System.Linq;
 
@@ -22,7 +23,8 @@ namespace Falcon.SugarApi
                       join t in target.GetType().GetProperties() on s.Name equals t.Name
                       select new { s, t };
             foreach (var item in all) {
-                item.t.SetValue(target, Convert.ChangeType(item.s.GetValue(source), item.t.PropertyType));
+                //item.t.SetValue(target, Convert.ChangeType(item.s.GetValue(source), item.t.PropertyType));
+                item.t.SetValue(target,item.s.GetValue(source).ChangeType(item.t.PropertyType));
             }
             return source;
         }
@@ -38,5 +40,25 @@ namespace Falcon.SugarApi
             source.CloneTo(target);
             return target;
         }
+
+        /// <summary>
+        /// 将对象转换成另一类型，如果转换失败可能返回null。
+        /// </summary>
+        /// <param name="source">原对象</param>
+        /// <param name="targetType">目标类型</param>
+        /// <returns>转换后的类型</returns>
+        public static object? ChangeType(this object? source,Type targetType) {
+            if (targetType == null) {
+                throw new ArgumentNullException("targetType");
+            }
+            if (source==null) {
+                return null;
+            }
+            if (targetType.IsGenericType && targetType.GetGenericTypeDefinition().Equals(typeof(Nullable<>))) {
+                NullableConverter nullableConverter = new NullableConverter(targetType);
+                targetType = nullableConverter.UnderlyingType;
+            }
+            return Convert.ChangeType(source, targetType);
+        }
     }
 }