StringBuilder的VS的XmlTextWriter

问题描述

我要挤尽可能多的表现，我可以从一个自定义的HttpHandler供应XML内容。

I am trying to squeeze as much performance as i can from a custom HttpHandler that serves Xml content.

我想知道这是更好的性能。使用XmlTextWriter类或临时StringBuilder的操作，如：

I' m wondering which is better for performance. Using the XmlTextWriter class or ad-hoc StringBuilder operations like:

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

有没有人有第一手的经验？

Does anyone have first hand experience?

推荐答案

由于乔希说，这是，如果你还没有证明其必要性，你应该甚至不考虑微的优化。它也确实不难测试：

As Josh said, this is a micro-optimization that you shouldn't even consider if you haven't proved its necessity. It's also really not difficult to test:

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();
}

不仅是的XmlWriter 版本始终由一个或两个毫秒的速度更快，它产生格式良好的XML，这另一种方法则没有。

Not only is the XmlWriter version consistently faster by a millisecond or two, it produces well-formed XML, which the other method doesn't.

不过，这两种方法都创造10万XML元素文件在我二十岁的笔记本电脑，那不断下降微不足道与它会通过网络推这么多数据的时间相比，时间量大约60毫秒。

But both methods are creating 100,000-element XML documents in about 60 milliseconds on my two-year-old laptop, an amount of time that dwindles into insignificance compared with the time it will take to push that much data over the network.

这篇关于StringBuilder的VS的XmlTextWriter的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！