实时获取网络时间 并转换为北京时间的函数

unit Unit1;



interface



uses

  Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,

  Vcl.Controls, Vcl.Forms, Vcl.Dialogs,Winapi.msxml, System.DateUtils,

  Vcl.StdCtrls;



type

  TForm1 = class(TForm)

    Button1: TButton;

    Label1: TLabel;

    Label2: TLabel;

    procedure Button1Click(Sender: TObject);

  private

    { Private declarations }

  public

    { Public declarations }

  end;



var

  Form1: TForm1;



implementation



{$R *.dfm}

//实时获取网络时间的函数, 得到的是格林威治时间; 默认从 sohu 服务器获取, 因为它最快, 平均只需 15 毫秒

function GetNetTime(aUrl: WideString = 'http://www.sohu.com'): string;

begin

  with CoXMLHTTP.Create do

  begin

    open('Post', aUrl, False, EmptyParam, EmptyParam);

    send(EmptyParam);

    Result := getResponseHeader('Date');

  end;

end;



//格林威治时间(字符串)转换到北京时间  1

function GMT2BjDateTime(const GMT: string): TDateTime;

var

  A: TArray<string>;

begin

  A := GMT.Split([',', ' '], ExcludeEmpty); //XE4 支持



  with TStringList.Create do begin

    CommaText := 'Jan=1,Feb=2,Mar=3,Apr=4,May=5,Jun=6,Jul=7,Aug=8,Sep=9,Oct=10,Nov=11,Dec=12';

    A[2] := Values[A[2]];

    Free;

  end;



  Result := StrToDateTime(Format('%s/%s/%s %s', [A[3], A[2], A[1], A[4]]), FormatSettings.Create(2052));

  Result := Result + 8/24; //换算成北京时间

end;

//格林威治时间(字符串)转换到北京时间  2

function GMT2BjDateTime2(const GMT: string): TDateTime;

var

  A: TArray<string>;

begin

  A := GMT.Split([',', ' '], ExcludeEmpty); //XE4 支持



  with TStringList.Create do begin

    CommaText := 'Jan=1,Feb=2,Mar=3,Apr=4,May=5,Jun=6,Jul=7,Aug=8,Sep=9,Oct=10,Nov=11,Dec=12';

    A[2] := Values[A[2]];

    Free;

  end;



  Result := StrToDateTime(Format('%s/%s/%s %s', [A[3], A[2], A[1], A[4]]), FormatSettings.Create(2052));

  Result := Result + 8/24; //换算成北京时间

end;

procedure TForm1.Button1Click(Sender: TObject);

var

  strGMT: string;

  bjDateTime: TDateTime;

  bjDateTime2: TDateTime;

begin

  strGMT := GetNetTime();

  bjDateTime := GMT2BjDateTime(strGMT);

  bjDateTime2 := GMT2BjDateTime2(strGMT);



  Label1.Caption:=strGMT + #10 + DateTimeToStr(bjDateTime);

  Label2.Caption:=strGMT + #10 + DateTimeToStr(bjDateTime2);

end;







end.