xml文件操作(50分)

delphi 可以对xml文件的数据进行分组统计吗？
现在仅是能用clientdataset 对 xml文件读出显示
怎么实现分组统计？

~关注~~~~~~~~
~帮顶~~~~~~

什么样的分组统计？

能不能像对数据表操作那样用：
select table group by

不会没有办法吧，难道要将数据导入数据库中才能用sql吗？

用cxGrid控件

用listview

procedure TForm1.btnImportXMLClick(Sender: TObject);
// Read XML from TMemo and convert into record structure
var
i: integer;
ADoc: TNativeXml;
ANode: TXmlNode;
AList: TList;
begin
ADoc := TNativeXml.Create;
try
// Read from memo
ADoc.ReadFromString(mmXML.Text);

// A temporary list to hold references to the record elements
AList := TList.Create;
try
ANode := ADoc.Root.NodeByName('fields');
if not assigned(ANode) then exit;

// List of nodes that are named "field"
ANode.NodesByName('field', AList);

// Set dynamic array length
SetLength(Fields, AList.Count);

// Import each element
for i := 0 to AList.Count - 1 do
LoadFieldFromNode(Fields, AList);

// Show table
lvTable.Items.Count := AList.Count;
lvTable.Invalidate;

// Status
lbStatus.Caption := Format('Imported %d records', [AList.Count]);

finally
AList.Free;
end;
finally
ADoc.Free;
end;
end;

procedure TForm1.LoadFieldFromNode(var AField: FieldRecord;
ANode: TXmlNode);
// Load one field from the XML element ANode
var
i: integer;
AMeta: TXmlNode;
AEnum: TXmlNode;
AList: TList;
begin
with AField, ANode do begin
// Initialize record
FillChar(AField, SizeOf(AField), 0);

// The flat data
FieldId := AttributeByName['id'];
FieldReq := AttributeByName['required'];
FieldType := AttributeByName['type'];
FieldCap := ReadString('caption');
DependField := AttributeByName['dependsfield'];

// Meta data
AMeta := NodeByName('metadata');
if assigned(AMeta) then with AMeta do begin
MetaType := AttributeByName['type'];

// List that holds enumeration
AList := TList.Create;
try

// "enum" metadata
if MetaType = 'enum' then begin
AEnum := NodeByName('enumeration');
if assigned(AEnum) then
AEnum.NodesByName('enumvalue', AList);
// all enumeration values
for i := 0 to AList.Count - 1 do with TXmlNode(AList) do
MetaData := MetaData +
AttributeByName['id'] + ',' + ReadString('caption') + ';';
end;

// "hashtable" metadata
if MetaType = 'hashtable' then begin
AEnum := NodeByName('hashtable');
if assigned(AEnum) then
AEnum.NodesByName('code', AList);
// all enumeration values
for i := 0 to AList.Count - 1 do with TXmlNode(AList) do
MetaData := MetaData +
AttributeByName['id'] + ',' + ValueAsString + ';';
end;

finally
AList.Free;
end;
end;
end;
end;

procedure TForm1.lvTableData(Sender: TObject; Item: TListItem);
// Add data to each item in the listview. We use the listview with OwnerData
begin
if (Item.Index >= 0) and (Item.Index < Length(Fields)) then begin
with Fields[Item.Index] do begin
Item.Caption := FieldID;
Item.SubItems.Add(FieldReq);
Item.SubItems.Add(FieldType);
Item.SubItems.Add(FieldCap);
Item.SubItems.Add(DependField);
Item.SubItems.Add(MetaType);
Item.SubItems.Add(MetaData);
end;
end;
end;

end.