【学习】lazarus的Laz2_XMLCfg用法

lazarus的lpi等文件都是使用XML格式，使用Laz2_XMLCfg可以方便读写这类XML配置文件。
0、在uses添加Laz2_XMLCfg单元。
1、下面的例子是读取ProjectOptions/Units所有unit中FileName

<?xml version="1.0" encoding="UTF-8"?>
<CONFIG>
  <ProjectOptions>
    <Units>
      <Unit>
        <Filename Value="project1.lpr"/>
        <IsPartOfProject Value="True"/>
      </Unit>
      <Unit>
        <Filename Value="unit1.pas"/>
        <IsPartOfProject Value="True"/>
        <ComponentName Value="Form1"/>
        <HasResources Value="True"/>
        <ResourceBaseClass Value="Form"/>
        <UnitName Value="Unit1"/>
      </Unit>
      <Unit>
        <Filename Value="unit2.pas"/>
      </Unit>
    </Units>
  </ProjectOptions>
</CONFIG>

procedure TForm1.Button5Click(Sender: TObject);
var
  XMLConfig: TXMLConfig;
  s:String;
  i,n,NewUnitCount:Integer;
  LegacyList: Boolean;
  SubPath: String;
  NewUnitFilename,Path: String;
begin
  Memo1.Lines.Clear;
  Memo1.Lines.Add('');
  Path:='ProjectOptions/';
  XMLConfig:=TXMLConfig.Create('project2.lpi');
  n:=XMLConfig.GetChildCount('ProjectOptions/Units');
  LegacyList:= XMLConfig.IsLegacyList('ProjectOptions/Units/');
  NewUnitCount:=XMLConfig.GetListItemCount('ProjectOptions/Units/', 'Unit', LegacyList);
  for i := 0 to NewUnitCount - 1 do begin
    SubPath:=Path+'Units/'+XMLConfig.GetListItemXPath('Unit', i, LegacyList)+'/';
    NewUnitFilename:=XMLConfig.GetValue(SubPath+'Filename/Value','');
    Memo1.Lines.Add(NewUnitFilename);
  end;
  XMLConfig.Flush;
  XMLConfig.Free;
end;

 2、在Units添加一下unit,FileName='Unit2.pas'

procedure TForm1.Button6Click(Sender: TObject);
var
  XMLConfig: TXMLConfig;
  s:String;
  i,n,NewUnitCount:Integer;
  LegacyList: Boolean;
  SubPath: String;
  NewUnitFilename,Path: String;
begin
  Path:='ProjectOptions/';
  XMLConfig:=TXMLConfig.Create('project2.lpi');
  n:=XMLConfig.GetChildCount(path+'Units');
  LegacyList:= XMLConfig.IsLegacyList(path+'Units/');
  NewUnitCount:=XMLConfig.GetListItemCount(path+'Units/', 'Unit', LegacyList);//读取Units的unit数量
  //在原有的Units添加1个Unit
  i:=NewUnitCount;
  SubPath:=Path+'Units/'+XMLConfig.GetListItemXPath('Unit', i, LegacyList)+'/';
  XMLConfig.SetValue(SubPath+'Filename/Value','unit2.pas');
  XMLConfig.Flush;
  XMLConfig.Free;
end;

3、删除第2个Unit

procedure TForm1.Button3Click(Sender: TObject);
var
  XMLConfig: TXMLConfig;
begin
  XMLConfig:=TXMLConfig.Create('project2.lpi');
  XMLConfig.DeletePath('ProjectOptions/Units/Unit[2]');
  XMLConfig.Flush;
  XMLConfig.Free;
end;

4、删除第2个unit的FileName

procedure TForm1.Button2Click(Sender: TObject);
var
  XMLConfig: TXMLConfig;
begin
  XMLConfig:=TXMLConfig.Create('project2.lpi');
  XMLConfig.DeleteValue('ProjectOptions/Units/Unit[2]/Filename/Value');
  XMLConfig.Flush;
  XMLConfig.Free;
end;

 4、读第2个Unit的Filename

procedure TForm1.Button7Click(Sender: TObject);
var
  XMLConfig: TXMLConfig;
  Path:String;
begin
  Path:='ProjectOptions/';
  XMLConfig:=TXMLConfig.Create('project2.lpi');
  Memo1.Lines.Add(XMLConfig.GetValue(Path+'Units/Unit[2]/Filename/Value',''));
  XMLConfig.Flush;
  XMLConfig.Free;
end;