事件没有被解雇

Question

我试图使用WebWorkerStarted并WebWorkerFinished从TWebbrowser然而事件只是不明白在所有被解雇.

我怎样才能使这些活动有效？我想看看哪些工作线程正在启​​动TWebbrowser.

unit Unit2;

interface

uses
  Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
  Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, Vcl.OleCtrls, SHDocVw;

type
  TForm2 = class(TForm)
    WebBrowser1: TWebBrowser;
    Button1: TButton;
    procedure Button1Click(Sender: TObject);
    procedure WebBrowser1WebWorkerFinsihed(ASender: TObject; dwUniqueID: Cardinal);
    procedure WebBrowser1WebWorkerStarted(ASender: TObject; dwUniqueID: Cardinal; const bstrWorkerLabel: WideString);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form2: TForm2;

implementation

{$R *.dfm}

procedure TForm2.Button1Click(Sender: TObject);
begin
  WebBrowser1.Navigate('www.stackoverflow.com');
end;

procedure TForm2.WebBrowser1WebWorkerFinsihed(ASender: TObject; dwUniqueID: Cardinal);
begin
  // does not fire
end;

procedure TForm2.WebBrowser1WebWorkerStarted(ASender: TObject; dwUniqueID: Cardinal; const bstrWorkerLabel: WideString);
begin
  // does not fire
end;

end.

Answer 1

如此处所述:

默认情况下,即使运行时环境安装了最新的IE(例如,IE11),TWebBrowser也会使用IE7标准模式.

WebWorkers是在IE10中引入的,因此您必须让IE以更新的模式运行.至少需要设置两个注册表项(如果同时支持32/64位,则更多):

HKEY_LOCAL_MACHINE (or HKEY_CURRENT_USER) 
  {\Wow6432Node}
  \SOFTWARE
  \Microsoft 
  \Internet Explorer
  \Main
  \FeatureControl
  \FEATURE_BEHAVIORS
     {NEW DWORD ->  'YourApplication.exe'
     {    VALUE -> 1  

另外(例如,IE11模式)

  HKEY_LOCAL_MACHINE (or HKEY_CURRENT_USER) 
  {\Wow6432Node}
  \SOFTWARE
  \Microsoft 
  \Internet Explorer
  \Main
  \FeatureControl
  \FEATURE_BROWSER_EMULATION
     {NEW DWORD ->  'YourApplication.exe'
     {    VALUE ->  0x2AF8 

这将导致由TWebBrowser包装的Internet Explorer实例以IE11模式运行,支持WebWorkers等.在设置此值之前,您应该对安装的IE版本进行某种健全性检查.有关有效条目的更多信息,请访问MSDN.

WebWorker导航到StackOverflow时,这仍然不会引发任何事件(你确定它使用它们吗？).作为验证测试​​,此WebWorkers演示页面确实引发了一个OnWebWorkerStarted事件:

WebBrowser1.Navigate('https://whatwg.org/demos/workers/primes/page.html');