can anyone help me to learn how to use XML. As a test i want to use XML instead of INI files for saving a program settings.
Thanks
Rigo, you can use the IXMLDocument interface or the TXMLDocument object to interact with a XML document.
You can check these links for more information about XML and Delphi
Check this sample code , to learn the basics about xml management using the IXMLDocument interface.
program Delphi_XmlSaveSettings;
{$APPTYPE CONSOLE}
uses
ActiveX,
SysUtils,
XmlDoc,
XmlIntf;
//this class mimic the basics functionalities of an TIniFile
//you can improve a lot the code adding exception handling and more methods for specifics tasks.
type
TXMLSettings = class
private
FFileName: string;
FXMLDoc: IXMLDocument; //Main XMLObject
public
constructor Create(const FileName: string); overload;
destructor Destroy; override;
function ReadString(const Section, Key, default: string): string;
procedure WriteString(const Section, Key, Value: string);
function ReadInteger(const Section, Key: string; default: Integer): Integer;
procedure WriteInteger(const Section, Key: string; Value: Integer);
function ReadBoolean(const Section, Key: string; default: Boolean): Boolean;
procedure WriteBoolean(const Section, Key: string; Value: Boolean);
function ReadDouble(const Section, Key: string; default: Double): Double;
procedure WriteDouble(const Section, Key: string; Value: Double);
function ReadDateTime(const Section, Key: string; default: TDatetime): TDateTime;
procedure WriteDatetime(const Section, Key: string; Value: TDatetime);
function ReadDate(const Section, Key: string; default: TDatetime): TDateTime;
procedure WriteDate(const Section, Key: string; Value: TDatetime);
procedure Save;
end;
constructor TXMLSettings.Create(const FileName: string);
begin
inherited Create;
FFileName := FileName;
FXMLDoc := NewXMLDocument; //Create aNew instance of a XML Document
FXMLDoc.Encoding:= 'UTF-8'; //Set the encoding
FXMLDoc.Options := [doNodeAutoIndent];//optional, is used to indent the Xml document
if FileExists(FFileName) then
FXMLDoc.LoadFromFile(FFileName)
else
FXMLDoc.AddChild('Root'); //Create the root Node
end;
destructor TXMLSettings.Destroy;
begin
Save;
inherited;
end;
function TXMLSettings.ReadBoolean(const Section, Key: string; default: Boolean): Boolean;
begin
Result := Boolean(ReadInteger(Section, Key, Integer(default)));
end;
function TXMLSettings.ReadDate(const Section, Key: string; default: TDatetime): TDateTime;
begin
Result := StrToDate(ReadString(Section, Key, DateToStr(default)));
end;
function TXMLSettings.ReadDateTime(const Section, Key: string; default: TDatetime): TDateTime;
begin
Result := StrToDateTime(ReadString(Section, Key, DateTimeToStr(default)));
end;
function TXMLSettings.ReadDouble(const Section, Key: string; default: Double): Double;
begin
Result := StrToFloat(ReadString(Section, Key, FloatToStr(default)));
end;
function TXMLSettings.ReadInteger(const Section, Key: string; default: Integer): Integer;
begin
Result := StrToInt(ReadString(Section, Key, IntToStr(default)));
end;
function TXMLSettings.ReadString(const Section, Key, default: string): string;
var
XMLNode: IXMLNode;
begin
XMLNode := FXMLDoc.DocumentElement.ChildNodes.FindNode(Section);
if Assigned(XMLNode) and XMLNode.HasAttribute(Key) then //Check if exist the Key
Result := XMLNode.Attributes[Key]
else
Result := default;
end;
procedure TXMLSettings.Save;
begin
FXMLDoc.SaveToFile(FFileName);
end;
procedure TXMLSettings.WriteBoolean(const Section, Key: string; Value: Boolean);
begin
WriteInteger(Section, Key, Integer(Value));
end;
procedure TXMLSettings.WriteDate(const Section, Key: string; Value: TDatetime);
begin
WriteString(Section, Key, DateToStr(Value));
end;
procedure TXMLSettings.WriteDatetime(const Section, Key: string; Value: TDatetime);
begin
WriteString(Section, Key, DateTimeToStr(Value));
end;
procedure TXMLSettings.WriteDouble(const Section, Key: string; Value: Double);
begin
WriteString(Section, Key, FloatToStr(Value));
end;
procedure TXMLSettings.WriteInteger(const Section, Key: string; Value: Integer);
begin
WriteString(Section, Key, IntToStr(Value));
end;
procedure TXMLSettings.WriteString(const Section, Key, Value: string);
var
XMLNode: IXMLNode;
begin
XMLNode := FXMLDoc.DocumentElement.ChildNodes.FindNode(Section);
if not Assigned(XMLNode) then
XMLNode := FXMLDoc.DocumentElement.AddChild(Section);
XMLNode.Attributes[Key] := Value;
end;
Procedure SaveSettings; //Store the settings
Var
AppSettings : TXMLSettings;
begin
AppSettings:=TXMLSettings.Create(ExtractFilePath(ParamStr(0))+'MySettings.xml');
try
AppSettings.WriteString('Server','Type','SQLServer');
AppSettings.WriteString('Server','User','root');
AppSettings.WriteInteger('Server','port',1433);
AppSettings.WriteString('Server','IP','192.168.1.1');
AppSettings.WriteString('Server','Database','Prod');
AppSettings.WriteBoolean('Server','WindowsAuth',False);
AppSettings.WriteDouble('Server','Latency',25.90892);
AppSettings.WriteDatetime('Server','LastAccess',Now);
AppSettings.WriteDate('Server','ActualDate',Now);
AppSettings.Save;
finally
AppSettings.Free;
end;
Writeln('Settings Saved');
end;
Procedure ShowSettings;//Read the settings
Var
AppSettings : TXMLSettings;
begin
AppSettings:=TXMLSettings.Create(ExtractFilePath(ParamStr(0))+'MySettings.xml');
try
Writeln(Format('Type %s',[AppSettings.ReadString('Server','Type','')]));
Writeln(Format('Port %d',[AppSettings.ReadInteger('Server','port',0)]));
Writeln(Format('IP %s',[AppSettings.ReadString('Server','IP','')]));
Writeln(Format('Database %s',[AppSettings.ReadString('Server','Database','')]));
Writeln(Format('WindowsAuth %s',[BoolToStr(AppSettings.ReadBoolean('Server','WindowsAuth',True),True)]));
Writeln(Format('Latency %g',[AppSettings.ReadDouble('Server','Latency',0)]));
Writeln(Format('LastAccess %s',[DateTimeToStr(AppSettings.ReadDateTime('Server','LastAccess',Now-1))]));
Writeln(Format('ActualDate %s',[DateToStr(AppSettings.ReadDate('Server','ActualDate',Now-1))]));
finally
AppSettings.Free;
end;
end;
begin
try
CoInitialize(nil); //only necesary in console applications
try
SaveSettings; //Save the sample settings
ShowSettings; //Read the stored settings
Readln;
finally
CoUninitialize; //only necesary in console applications
end;
except
on E:Exception do
Writeln(E.Classname, ': ', E.Message);
end;
end.