最近在使用.NET當中的序列化方法序列化字串時碰到一個小問題。序列化時一切正常，反序列化時卻

碰到了問題。
先看程式碼:

//物件定義 [Serializable] public class TestObject { public string Value { get; set; } } #region XmlFormatter 序列化類 /// <summary> /// 序列化類 /// </summary> public class XmlFormatter { public static string ToXml(object obj) { if (obj == null) return string.Empty; StringBuilder sb = new StringBuilder(); StringWriter sw = new StringWriter(sb); try { XmlSerializer serializer = new XmlSerializer(obj.GetType(), string.Empty); serializer.Serialize(sw, obj); sw.Close(); return sb.ToString(); } catch (Exception ex) { Debug.WriteLine(ex); return string.Empty; } } public static object FromXml(string xml, Type type) { try { StringReader reader = new StringReader(xml); XmlSerializer serializer = new XmlSerializer(type); object obj = serializer.Deserialize(reader); reader.Close(); return obj; } catch (Exception ex) { Debug.WriteLine(ex); } return null; } } #endregion //測試程式碼 //普通的字串 static void TestMethod1() { TestObject expected = new TestObject() { Value = "Test 1234" }; string xmlString = XmlFormatter.ToXml(expected); TestObject actual = new TestObject(); actual = (TestObject)XmlFormatter.FromXml(xmlString, actual.GetType()); if (actual != null && expected.Value == actual.Value) Console.WriteLine("TestClass1.TestMethod1 passed!"); else Console.WriteLine("TestClass1.TestMethod1 failed!"); } //包含特殊字元的字串 static void TestMethod2() { TestObject expected = new TestObject() { Value = "Test1234" }; string xmlString = XmlFormatter.ToXml(expected); TestObject actual = new TestObject(); actual = (TestObject)XmlFormatter.FromXml(xmlString, actual.GetType()); if (actual != null && expected.Value == actual.Value) Console.WriteLine("TestClass1.TestMethod2 passed!"); else Console.WriteLine("TestClass1.TestMethod2 failed!"); }

輸出結果：
TestClass1.TestMethod1 passed!
TestClass1.TestMethod2 failed!

Debug發現TestMethod1的序列化結果是：

<?xml version="1.0" encoding="utf-16"?> <TestObject xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema"> <Value>Test 1234</Value> </TestObject>

TestMethod2的序列化結果是：

<?xml version="1.0" encoding="utf-16"?> <TestObject xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema"> <Value>Test&#x1;&#x2;&#x3;&#x4;1234</Value> </TestObject>

如果我們把TestMethod2的這段Xml存為一個檔案，然後用Visual Studio開啟，會發現有以下的錯誤提示：

Error 3 Character ' ', hexadecimal value 0x1 is illegal in XML documents. XMLFile2.xml 3 14 Miscellaneous Files
Error 4 Character ' ', hexadecimal value 0x2 is illegal in XML documents. XMLFile2.xml 3 19 Miscellaneous Files
Error 5 Character ' ', hexadecimal value 0x3 is illegal in XML documents. XMLFile2.xml 3 24 Miscellaneous Files
Error 6 Character ' ', hexadecimal value 0x4 is illegal in XML documents. XMLFile2.xml 3 29 Miscellaneous Files

這下我們明白了，原來就是：...這些個特殊字元在作怪。網上搜了一把，這個過程比較鬱悶，不知道該用什麼關鍵字去搜，後來直接在Google裡試了一下“&#x1”發現前兩個就是和我相似的問題，其中第一個裡面講到了MSDN裡面的原文

參考這裡吧：

特別是MSDN的原文：

這下就明白了，我反序列化的時候沒有直接用到XmlTextReader，而Normalization預設是true，而是用的StringReader把字串讀取為流，只要把反序列化的方法稍微改改就行：

 TextReader tr = new StringReader(xml); XmlTextReader reader = new XmlTextReader(tr); reader.Normalization = false; XmlSerializer serializer = new XmlSerializer(type); object obj = serializer.Deserialize(reader); tr.Close(); reader.Close(); return obj ;

好了，完事大吉！

最後奉上測試程式碼：測試程式碼