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如下所示，最新的 NativeXml (v4.03 svn) 将元素的值分为三部分：前面的空白、char 数据和尾随空白。因此，可以迭代地检查元素的子节点以获取带有前后空格的值。但是，对于传统的 NativeXml (v3.10)，这不是必需的，因此我想知道这样做的首选方式是什么（可能没有这种迭代检查/字符串连接）？

示例 XML 文档

<?xml version="1.0" encoding="UTF-8" ?>
<CDXML><s>beforeLineBreak
</s></CDXML>

示例 XML 文档

<?xml version="1.0" encoding="UTF-8" ?>
<CDXML><s>
afterLineBreak</s></CDXML>

使用不需要迭代检查的 NativeXml v3.10 的示例代码

procedure XXX310;
var
  element: TXmlNode; 
  elementType: TElementType;
begin
  elementType := element.ElementType;
  element.ElementType := xeCharData;
  ... element.ValueAsString ...
  element.ElementType := elementType;      
end;

NativeXml v3.10相关源码（完整方法体）

function TXmlNode.GetValueAsString: UTF8String;
begin
  if FElementType = xeNormal then
    Result := UnEscapeString(sdUTF8Trim(FValue))
  else
    Result := UnEscapeString(FValue);
end;

使用需要迭代检查的 NativeXml v4.03 svn 的示例代码

procedure XXX403;
var
  tempString: String;
  element: TXmlNode; // actually TsdElement
begin
  tempString := '';
  for I := element.DirectNodeCount to element.NodeCount - 1 do
    if element.Nodes[I] is TsdCharData then
       tempString := tempString + (element.Nodes[I] as TsdCharData).Value;

  ... tempString ...
end;

NativeXml v4.03 svn相关源码（不完整的类型声明或方法体）

unit NativeXml;
interface

  // TXmlNode is the ancestor for all nodes in the xml document. See TsdElement
  // for the elements, TsdAttribute for the attributes.
  TXmlNode = class(TDebugPersistent)
  Public
    // The value of the node. For elements this is the element value (based on
    // first chardata fragment), for attributes this is the attribute value. The
    // string is encoded as UTF8. Use ToWide(Node.Value) or Node.ValueUnicode
    // to get a UnicodeString compatible with "unicode" windows methods.
    property Value: Utf8String read GetValue write SetValue;
  end;

  // Node representing an xml element.
  TsdElement = class(TsdContainerNode)
  protected
    // parses the value in descendants TsdElement and TsdDocType
    procedure ParseIntermediateData(P: TsdXmlParser); override;
  end;

implementation

function TsdElement.GetValue: Utf8String;
begin
  // Return the value of the CharData subnode designated by the parser
  if (FValueIndex >= 0) and (FValueIndex < FNodes.Count) then
  begin
    // chardata value at FValueIndex
    // This calls TsdCharData.GetValue(),
    // then TsdCharData.GetCoreValue().
    Result := FNodes[FValueIndex].Value;

    // do un-normalisation if mac/windows
    if GetEolStyle <> esLF then
      Result := sdUnNormaliseEol(Result, GetEolStyle);

  end else
    // default value
    Result := '';
end;

procedure TsdElement.ParseIntermediateData(P: TsdXmlParser);  
begin  
  CharDataString := sdTrim(S, PreString, PostString);

  if GetPreserveWhiteSpace and (Length(PreString) > 0) then
  begin
    WhiteSpaceNode := TsdWhiteSpace.Create(TNativeXml(FOwner));
  end;

  if length(CharDataString) > 0 then
  begin
    // Insert CharData node
    CharDataNode := TsdCharData.Create(TNativeXml(FOwner));
  end;  

  if GetPreserveWhiteSpace and (Length(PostString) > 0) then
  begin
    WhiteSpaceNode := TsdWhiteSpace.Create(TNativeXml(FOwner));
  end;
end;

end.
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