Delphi中怎么对XML中任意节点进行添加、修改、删除、查询等操作？

Delphi中如何对XML中任意节点进行添加、修改、删除、查询等操作？急。
如题，

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http://60.28.222.210/dispbbs.asp?boardID=11&ID=23546
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不知道,帮顶!
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NativeXML
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参考：（也可以注册成控件用）

unit XmlHelper;

interface

uses
Windows, Messages, SysUtils, Variants, Classes,Dialogs,Graphics,Controls,Forms,ComCtrls,
StdCtrls,ExtCtrls,xmldom, XMLDoc, XMLIntf,Math,Contnrs;

type

TXmlNodeObject = class(TObject)
public
XmlNode : IXmlNode;
end;

//-----------------------------------------------
// Xml装载方式
//
//-----------------------------------------------
TXmlLoadType = (FromString,FromLocalFile,FromURL);

TXmlHelper = class(TObject)
private
m_XmlDoc: IXmlDocument;
m_sLastErrorMessage: WideString;

function GetDocument:IXmlDocument;
function GetEncoding:WideString;
procedure SetEncoding(const Value: WideString);
function GetRootNode: IXmlNode;

public
Constructor Create;overload;
Constructor Create(xmlDoc:IXmlDocument);overload;
Destructor Free;

property Document:IXmlDocument read GetDocument;
property Encoding:WideString read GetEncoding write SetEncoding;
property RootNode:IXmlNode read GetRootNode;

function SaveToFile(sTargetFileName : WideString):Boolean;
function GetXmlString: WideString;
function LoadXML(sourceXMLOrFile:WideString;loadType:TXmlLoadType):Boolean;


function GetAttributeValue(node : IXmlNode; sAttributeName : WideString):WideString;
function GetAttributeInt32(node : IXmlNode; sAttributeName : WideString):Integer;
function GetAttributeDouble(node : IXmlNode; sAttributeName : WideString):Double;
function GetAttributeBoolean(node : IXmlNode; sAttributeName : WideString):Boolean;

function GetElementValue(node : IXmlNode):WideString;
function GetElementInt32(node : IXmlNode):Integer;
function GetElementDouble(node : IXmlNode):Double;
function GetElementBoolean(node : IXmlNode):Boolean;

function GetChildElementValue(parentNode : IXmlNode;sElementName : WideString):WideString;
function GetChildElementInt32(parentNode : IXmlNode;sElementName : WideString):Integer;
function GetChildElementDouble(parentNode : IXmlNode;sElementName : WideString):Double;
function GetChildElementBoolean(parentNode : IXmlNode;sElementName : WideString):Boolean;


function GetFirstChildXmlNodeFromRoot(sElementName : WideString) : TXmlNodeObject;
function GetFirstChildXmlNode(parentNode : IXmlNode;sElementname : WideString) : IXmlNode;
function GetChildNodesFromRoot( sElementName : WideString ) : TObjectList;
function GetRecursiveChildNodesFromParent(parentNode : IXmlNode;sElementName : WideString) : TObjectList;

function CreateNodeElement(parentNode : IXmlNode ; sElementName,sElementValue : WideString) : IXmlNode;
//function CreateComment(insertAfterThisNode : IXmlNode;sVal : WideString) : IXmlNode;
//function CreateXmlDeclaration(sVersion,sEncoding,sStandalone : WideString) : IXmlNode;
function DeleteNodeElement(targetNode : IXmlNode) : Boolean;
function ModifyNodeElementValue(targetNode : IXmlNode;sNewElementValue : WideString) : Boolean;

function CreateNodeAttribute(targetNode : IXmlNode;sAttrName,sAttrValue : WideString) : Boolean;