Merge pull request #352 from hudingwen/master

xml序列化内存泄漏修复

Blog.Core.Common/Helper/XmlHelper.cs

@@ -1,33 +1,40 @@
 using System;
+using System.Collections.Concurrent;
 using System.Collections.Generic;
 using System.IO;
 using System.Xml.Serialization;
 
 namespace Blog.Core.Common.Helper
 {
+    /// <summary>
+    /// xml序列化帮助类
+    /// </summary>
     public class XmlHelper
     {
+        /// <summary>
+        /// 存储序列类型,防止内存泄漏
+        /// </summary>
+        private static ConcurrentDictionary<Type, XmlSerializer> hasTypes = new ConcurrentDictionary<Type, XmlSerializer>();
         /// <summary>
         /// 转换对象为JSON格式数据
         /// </summary>
         /// <typeparam name="T">类</typeparam>
         /// <param name="obj">对象</param>
         /// <returns>字符格式的JSON数据</returns>
-        public static string GetXML<T>(object obj)
+        public static string GetXML<T>(object obj, string rootName = "root")
         {
-            try
+            XmlSerializer xs;
+            var xsType = typeof(T);
+            hasTypes.TryGetValue(xsType, out xs);
+            if(xs == null)
             {
-                XmlSerializer xs = new XmlSerializer(typeof(T));
-
-                using (TextWriter tw = new StringWriter())
-                {
-                    xs.Serialize(tw, obj);
-                    return tw.ToString();
-                }
+                xs = new XmlSerializer(typeof(T));
+                hasTypes.TryAdd(xsType, xs);
             }
-            catch (Exception)
+            using (TextWriter tw = new StringWriter())
             {
-                return string.Empty;
+                xs.Serialize(tw, obj);
+                return tw.ObjToString();
             }
         }
 
@@ -37,15 +44,20 @@ namespace Blog.Core.Common.Helper
         /// <typeparam name="T"></typeparam>
         /// <param name="xml"></param>
         /// <returns></returns>
-        public static T ParseFormByXml<T>(string xml,string rootName="root")
+        public static T ParseFormByXml<T>(string xml, string rootName = "root")
         {
-            XmlSerializer serializer = new XmlSerializer(typeof(T), new XmlRootAttribute(rootName));
-            StringReader reader = new StringReader(xml);
-
-            T res = (T)serializer.Deserialize(reader);
-            reader.Close();
-            reader.Dispose();
-            return res; 
-        } 
+            XmlSerializer xs;
+            var xsType = typeof(T);
+            hasTypes.TryGetValue(xsType, out xs);
+            if (xs == null)
+            {
+                xs = new XmlSerializer(xsType, new XmlRootAttribute(rootName));
+                hasTypes.TryAdd(xsType, xs);
+            }
+            using (StringReader reader = new StringReader(xml))
+            {
+                return (T)xs.Deserialize(reader);
+            }
+        }
     }
 }