从API获取XML并将其存储在本地的最有效方法是什么?

我试图找到从韦氏词典中读取XML的最快方法，并将其存储到本地文件中以供以后使用。下面，我尝试实现一个模块，它做几件事:

1. 从本地目录读取2000个单词
2. 使用API
在merriam字典中查找每个单词
3. 将定义存储在本地XML中以供以后使用。

我不确定制作XML是否是存储这些数据的最佳方式，但它似乎是最简单的事情。起初，我想我会用不同的步骤来做。（1. 查找单词，存储单词和定义到数据结构中。2. 将所有数据转储为XML。)然而，这带来了一个问题，因为要在运行时(调用)堆栈上存储太多的东西。

因此，在这种情况下，我试图通过查找每个单词然后逐个保存到xml来加快速度。然而，这也是一个缓慢的方法。每写500-600字要花我10分钟。

public void load_module() // stores words/definitions into xml file
    { // 1. Pick up word from text file     2. Look up word's definition    3. Store in Xml 
        string workdirect = Directory.GetCurrentDirectory();
        workdirect = workdirect.Substring(0, workdirect.LastIndexOf("bin"));
        workdirect += "words1.txt";
        using (StreamReader read = new StreamReader(workdirect)) // 1. Pick up word from text file 
        {
            while (!read.EndOfStream)
            {
                string line = read.ReadLine(); 
                var definitions = load(line.ToLower());    // 2. Retrieve Words Definitions
                store_xml(line, definitions);
                wordlist.Add(line);
            }
        }
    }
    public List<string> load(string word)
    {
        XmlDocument doc = new XmlDocument();
        List<string> definitions = new List<string>();
        XmlNodeList node = null;
        doc.Load("http://www.dictionaryapi.com/api/v1/references/collegiate/xml/"+word+"?key=*****************"); // Asteriks to hide the actual API key
        if (doc.SelectSingleNode("entry_list").SelectSingleNode("entry").SelectSingleNode("def") == null)
        {
            return definitions;
        }
        node = doc.SelectSingleNode("entry_list").SelectSingleNode("entry").SelectSingleNode("def").SelectNodes("dt");
        // TO DO : implement definitions if there is no node "def" in first node entry "entry_list"
        foreach (XmlNode item in node)
        {
            definitions.Add(item.InnerXml.ToString().ToLower());
        }

        return definitions;
    }
    public void store_xml(string word, List<string> definitions)
    {
        string local = Directory.GetCurrentDirectory();
        string name = "dictionary_word.xml";
        local = local.Substring(0, local.LastIndexOf("bin"));
        bool exists = File.Exists(local + name);
        if (exists)
        {
            XmlDocument doc = new XmlDocument();
            doc.Load(local + name);
            XmlElement wordindoc = doc.CreateElement("Word");
            wordindoc.SetAttribute("xmlns", word);
            XmlElement defs = doc.CreateElement("Definitions");
            foreach (var item in definitions)
            {
                XmlElement def = doc.CreateElement("Definition");
                def.InnerText = item;
                defs.AppendChild(def);
            }
            wordindoc.AppendChild(defs);
            doc.DocumentElement.AppendChild(wordindoc);
            doc.Save(local+name);
        }
        else
        {
            using (XmlWriter writer = XmlWriter.Create(@local + name))
            {
                writer.WriteStartDocument();
                writer.WriteStartElement("Dictionary");
                writer.WriteStartElement("Word", word);
                writer.WriteStartElement("Definitions");
                foreach (var def in definitions)
                {
                    writer.WriteElementString("Definition", def);
                }
                writer.WriteEndElement();
                writer.WriteEndElement();
                writer.WriteEndElement();
                writer.WriteEndDocument();
            }
        }           
    }
}

public class Definition
{
    public string Word { get; set; }
    public string Definition { get; set; }
}

XmlWriterSettings settings = new XmlWriterSettings();
settings.Indent = true;
settings.IndentChars = ("    ");
settings.Encoding = Encoding.UTF8;
using (XmlWriter writer = XmlWriter.Create("C:'output'output.xml", settings))
{
    writer.WriteStartDocument();
    // TODO - use XMLWriter functions to write out each word and definition
    writer.Flush();
}