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.
