首先覺得利用XSLT還能過濾一些東西，然后再發送回客戶端，所以決定采用XSLT
　　然后就是嘗試寫一個換根的XSL，如下

<?xml version="1.0" encoding="gb2312" ?>
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:output method="xml" version="1.0" encoding="gb2312" omit-xml-declaration="yes" indent="yes" />

<xsl:template match="/">
<NEWNODENAME>
<xsl:apply-templates select="@* | node()" />
</NEWNODENAME>
</xsl:template>

<xsl:template match="@* | node()">
<xsl:choose>
<xsl:when test=".!=ancestor::node()"><xsl:copy><xsl:apply-templates select="@* | node()"/></xsl:copy></xsl:when>
<xsl:otherwise><xsl:apply-templates select="@* | node()"/></xsl:otherwise>
</xsl:choose>
</xsl:template>

</xsl:stylesheet>

大致意思是，解析一個XML中的所有結點及屬性，如果非根就直接拷貝，否則就查看是否存在子結點及屬性。具體資料請參照MSXML的SDK文檔。

　　然后寫一個函數，使得NEWNODENAME可以指定：

這段代碼為VB.Net中的實現，ASP中實現時需要注意對象附值需要用Set，還有返回值的問題

Public Function ChangeXmlRootNodeName(ByRef oXml As MSXML2.DOMDocument, ByVal name As String) As String
If oXml Is Nothing Then
Return ""
End If
Dim sXslt As String
sXslt = "<?xml version=""1.0"" encoding=""gb2312"" ?>" & vbCrLf
sXslt = sXslt & "<xsl:stylesheet version=""1.0"" xmlns:xsl=""http://www.w3.org/1999/XSL/Transform"">" & vbCrLf
sXslt = sXslt & "<xsl:output method=""xml"" version=""1.0"" encoding=""gb2312"" omit-xml-declaration=""yes"" indent=""yes"" />" & vbCrLf
sXslt = sXslt & vbCrLf
sXslt = sXslt & "<xsl:template match=""/"">" & vbCrLf
sXslt = sXslt & "<" & name & ">"" & vbCrLf"
sXslt = sXslt & " <xsl:apply-templates select=""@* | node()""/>" & vbCrLf
sXslt = sXslt & "</" & name & ">" & vbCrLf
sXslt = sXslt & "</xsl:template>" & vbCrLf
sXslt = sXslt & vbCrLf
sXslt = sXslt & "<xsl:template match=""@* | node()"">" & vbCrLf
sXslt = sXslt & " <xsl:choose>" & vbCrLf
sXslt = sXslt & " <xsl:when test="".!=ancestor::node()""><xsl:copy><xsl:apply-templates select=""@* | node()""/></xsl:copy></xsl:when>" & vbCrLf
sXslt = sXslt & " <xsl:otherwise><xsl:apply-templates select=""@* | node()""/></xsl:otherwise>" & vbCrLf
sXslt = sXslt & " </xsl:choose>"" & vbCrLf"
sXslt = sXslt & "</xsl:template>"" & vbCrLf"
sXslt = sXslt & vbCrLf
sXslt = sXslt & "</xsl:stylesheet>" & vbCrLf

Dim oXsl As New MSXML2.DOMDocument
oXsl.async = False
oXsl.resolveExternals = False
oXsl.loadXML(sXslt)

Dim sXml As String

sXml = oXml.transformNode(oXsl)

sXml = AddXmlHeader(sXml)

　sXsl = Nothing

Return sXml
End Function

　　還有，當然你也可以實現生成那個XSL的XSL文件，這就要看你如何設計了。