我想将 XmlDocument 对象的 xml 发送到 HTTP 客户端，但我担心 suggested soltuion 可能不遵守 Response 已设置为使用的编码:

public void ProcessRequest(HttpContext context)
{
   XmlDocument doc = GetXmlToShow(context);

   context.Response.ContentType = "text/xml";
   context.Response.ContentEncoding = System.Text.Encoding.UTF8;
   context.Response.Cache.SetCacheability(HttpCacheability.NoCache);
   context.Response.Cache.SetAllowResponseInBrowserHistory(true);

   doc.Save(context.Response.OutputStream);

public void ProcessRequest(HttpContext context)
{
   XmlDocument doc = GetXmlToShow(context);

   context.Response.ContentType = "text/xml";
   context.Response.ContentEncoding = System.Text.Encoding.Unicode;
   context.Response.Cache.SetCacheability(HttpCacheability.NoCache);
   context.Response.Cache.SetAllowResponseInBrowserHistory(true);

   doc.Save(context.Response.OutputStream);
}

context.Response.ContentEncoding = System.Text.Encoding.Unicode;
context.Response.Write("Hello World");

context.Response.ContentEncoding = System.Text.Encoding.UTF8;
context.Response.Write("Hello World");

context.Response.ContentEncoding = System.Text.Encoding.UTF16;
context.Response.Write("Hello World");

context.Response.ContentEncoding = System.Text.Encoding.ASCII;
context.Response.Write("Hello World");

context.Response.ContentEncoding = System.Text.Encoding.BigEndianUnicode;
context.Response.Write("Hello World");

最佳答案

我找到了。

答案是否定的:XmlDocument 不会遵守它写入的响应流的 ContentEncoding。

更新:正确的方法

public class Handler : IHttpHandler, System.Web.SessionState.IRequiresSessionState 
{
    //Note: We add IRequiesSessionState so that we'll have access to context.Session object
    //Otherwise it will be null


    public void ProcessRequest(HttpContext context)
    {
        XmlDocument doc = GetXmlToShow(context); //GetXmlToShow will look for parameters from the context

        if (doc != null)
        {
            context.Response.ContentType = "text/xml"; //must be 'text/xml'
            context.Response.ContentEncoding = System.Text.Encoding.UTF8; //we'd like utf-8
            doc.Save(context.Response.Output); //doc save itself to the textwriter, using the encoding of the text-writer (which comes from response.contentEncoding)
        }

        #region Notes
        /*
         * 1. Use Response.Output, and NOT Response.OutputStream.
         *    Both are streams, but Output is a TextWriter.
         *    When an XmlDocument saves itself to a TextWriter, it will use the encoding
         *    specified by the TextWriter. The XmlDocument will automatically change any
         *    xml declaration node, i.e.:
         *       <?xml version="1.0" encoding="ISO-8859-1"?>
         *    to match the encoding used by the Response.Output's encoding setting
         * 2. The Response.Output TextWriter's encoding settings comes from the 
         *    Response.ContentEncoding value.
         * 3. Use doc.Save, not Response.Write(doc.ToString()) or Response.Write(doc.InnerXml)
         * 3. You DON'T want to Save the xml to a string, or stuff the xml into a string
         *    and response.Write that, because that
         *     - doesn't follow the encoding specified
         *     - wastes memory
         * 
         * To sum up: by Saving to a TextWriter: the XML Declaration node, the XML contents,
         * and the HTML Response content-encoding will all match.
         */
        #endregion Notes
    }

    public bool IsReusable { get { return false; } }
}

     <?xml version="1.0" encoding="UTF-8"?>

<?xml version="1.0"?>

If an encoding attribute is not included, UTF-8 encoding is assumed when the document is written or saved out.

Unlike most XML attributes, encoding attribute values are not case-sensitive. This is because encoding character names follow ISO and Internet Assigned Numbers Authority (IANA) standards.

// Create an XML declaration. 
XmlDeclaration xmldecl;
xmldecl = doc.CreateXmlDeclaration("1.0", null, null);
xmldecl.Encoding="UTF-8";

// Add the new node to the document.
XmlElement root = doc.DocumentElement;
doc.InsertBefore(xmldecl, root);

The encoding on the TextWriter determines the encoding that is written out (The encoding of the XmlDeclaration node is replaced by the encoding of the TextWriter). If there was no encoding specified on the TextWriter, the XmlDocument is saved without an encoding attribute.

context.Response.ContentEncoding = System.Text.Encoding.ASCII;
doc.Save(context.Response.Output);

<?xml version="1.0" encoding="us-ascii" ?> 
<foo>Hello, world!</foo>

context.Response.ContentEncoding = System.Text.Encoding.UTF8;
doc.Save(context.Response.Output);

<?xml version="1.0" encoding="utf-8" ?> 
<foo>Hello, world!</foo>

context.Response.ContentEncoding = System.Text.Encoding.Unicode;
doc.Save(context.Response.Output);

<?xml version="1.0" encoding="utf-16" ?> 
<foo>Hello, world!</foo>

关于ASP.NET:将 XmlDocument 保存到 Response.OutputStream 会遵守编码吗？，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/546994/