C# · 12月 28, 2021

c# – StringBuilder与XmlTextWriter

我试图从提供Xml内容的自定义HttpHandler中尽可能多地提高性能.

我想知道哪个更好的性能.使用XmlTextWriter类或ad-hoc StringBuilder操作,如:

StringBuilder sb = new StringBuilder(“<?xml version=”1.0″ encoding=”UTF-8″ ?>”); sb.AppendFormat(“<element>{0}</element>”,SOMEVALUE);

有没有人有第一手经验?

解决方法 正如约什所说,这是一个微观优化,如果你没有证明它的必要性,你甚至不应该考虑.测试也非常困难: static void Main(string[] arguments){ const int iterations = 100000; Stopwatch sw = new Stopwatch(); sw.Start(); string s = CreateUsingStringBuilder(“content”,iterations); sw.Stop(); Console.WriteLine(String.Format(“CreateUsingStringBuilder: {0}”,sw.ElapsedMilliseconds)); sw.Reset(); sw.Start(); s = CreateUsingXmlWriter(“content”,iterations); sw.Stop(); Console.WriteLine(String.Format(“CreateUsingXmlWriter: {0}”,sw.ElapsedMilliseconds)); Console.ReadKey();}private static string CreateUsingStringBuilder(string content,int iterations){ StringBuilder sb = new StringBuilder(); for (int i = 0; i < iterations; i++ ) sb.AppendFormat(“<element>{0}</element>”,content); return sb.ToString();}private static string CreateUsingXmlWriter(string content,int iterations){ StringBuilder sb = new StringBuilder(); using (StringWriter sw = new StringWriter(sb)) using (XmlWriter xw = XmlWriter.Create(sw)) { xw.WriteStartElement(“root”); for (int i = 0; i < iterations; i++ ) xw.WriteElementString(“element”,content); xw.WriteEndElement(); } return sb.ToString();}

XmlWriter版本不仅速度提高了一两毫秒,而且还可以生成格式良好的XML,而另一种方法则不然.

但是这两种方法在我两年前的笔记本电脑上在大约60毫秒内创建了100,000个元素的XML文档,与通过网络推送大量数据所需的时间相比,这个时间缩短到了无足轻重的程度.