.net XmlSerialize抛出“无法在使用ConformanceLevel.Fragment创建的编写器上调用WriteStartDocument”

我试图序列化一个类，将XML文件写为多个片段，即将该类的每个对象写为单个片段，而不使用XML头/根。 以下是示例代码：

[Serializable] public class Test { public int X { get; set; } public String Y { get; set; } public String[] Z { get; set; } public Test() { } public Test(int x, String y, String[] z) { X = x; Y = y; Z = z; } } class Program { static void Main(string[] args) { Test t1 = new Test(1, "t1", new[] { "a", "b" }); Test t2 = new Test(2, "t2", new[] { "c", "d", "e" }); XmlSerializer serializer = new XmlSerializer(typeof(Test)); //using (StreamWriter writer = new StreamWriter(@"f:\test\test.xml")) { XmlWriter xmlWriter = XmlWriter.Create(@"f:\test\test.xml", new XmlWriterSettings() {ConformanceLevel = ConformanceLevel.Fragment, OmitXmlDeclaration = true, Indent = true}); serializer.Serialize(xmlWriter, t1); serializer.Serialize(xmlWriter, t2); xmlWriter.Close(); } } } 

在第一次序列化调用中，我得到了exception：

 WriteStartDocument cannot be called on writers created with ConformanceLevel.Fragment 

我在这里想念的是什么？

Answer 1

这个问题有一个解决方法。 在使用序列化程序之前使用xml writer时，将不会写入标头。 以下工作正常，但会在xml文件的第一行添加一个空注释标记

改进代码，如oleksa所建议的

 static void Main(string[] args) { Test t1 = new Test(1, "t1", new[] { "a", "b" }); Test t2 = new Test(2, "t2", new[] { "c", "d", "e" }); XmlSerializer serializer = new XmlSerializer(typeof(Test)); //using (StreamWriter writer = new StreamWriter(@"f:\test\test.xml")) { XmlWriter xmlWriter = XmlWriter.Create(@"test.xml", new XmlWriterSettings() { ConformanceLevel = ConformanceLevel.Fragment, OmitXmlDeclaration = false, Indent = true, NamespaceHandling = NamespaceHandling.OmitDuplicates }); xmlWriter.WriteWhitespace(""); serializer.Serialize(xmlWriter, t1); serializer.Serialize(xmlWriter, t2); xmlWriter.Close(); } }