是否通过XNA中的streamreader替换XML文件中的单词?

通过将整个XML文件读取到内存中并按照自己的方式处理,您可以非常巧妙地做到这一点:

string content = "";

// Read the XML file into content
StreamReader reader = new StreamReader("file.xml");
content = reader.ReadToEnd();
reader.Close();

// Find the character position just after the <?xml token, and just before the ?> token
int openIndex = content.IndexOf("<?xml", StringComparison.OrdinalIgnoreCase) + 5;
int closeIndex = content.IndexOf("?>", openIndex);

// Get the bits between <?xml and ?>    
string header = content.Substring(openIndex, closeIndex - openIndex);

// Substitute version string.
header = header.Replace("version=\"1.1\"", "version=\"1.0\"");

// Put Humpty Dumpty back together again.
content = string.Concat(content.Substring(0, openIndex), header, content.Substring(closeIndex));

// Feed content into an XMLReader (or equivalent) here.

它适用于您提供的示例字符串,但我还没有在格式不完善的XML文档上对其进行测试。