• 终止TTask.Run启动的线程


    unit Unit15;
    
    interface
    
    uses
      Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants,
      System.Classes, Vcl.Graphics,
      Vcl.Controls, Vcl.Forms, Vcl.Dialogs, System.Threading,
      kbmmwprocess, Vcl.StdCtrls, kbmMWClientDataset;
    
    type
      TForm15 = class(TForm)
        Button1: TButton;
        kbmMWClientTransactionResolver1: TkbmMWClientTransactionResolver;
        Button2: TButton;
        Label1: TLabel;
        procedure Button1Click(Sender: TObject);
        procedure FormCreate(Sender: TObject);
        procedure Button2Click(Sender: TObject);
      private
        FTaskIsRunning: boolean;
        cnt: Integer;
        { Private declarations }
      public
        { Public declarations }
      end;
    
    var
      Form15: TForm15;
    
    implementation
    
    {$R *.dfm}
    
    procedure TForm15.Button1Click(Sender: TObject);
    begin
      FTaskIsRunning := true;
      TTask.Run(
        procedure
        begin
          while FTaskIsRunning do
          begin
            sleep(99);
            TThread.Synchronize(nil,
              procedure
              begin
                Label1.Caption := 'Thread is running...' + cnt.ToString;
                inc(cnt);
              end);
          end;//end while.
        end);
    
    end;
    
    procedure TForm15.Button2Click(Sender: TObject);
    begin
      FTaskIsRunning := false;
      cnt := 0;
    end;
    
    procedure TForm15.FormCreate(Sender: TObject);
    begin
      FTaskIsRunning := false;
      cnt := 0;
    end;
    
    end.

    上面的代码,运行正常,按Button1开启一个线程,Button2终止线程运行。这是一个VCL项目。可以看到用一个私有变量FTaskIsRunning来控件线程中的循环。这个实现是在一个Form中,运行正常,现在换成TFrame中实现,基本上是复制Form中的实现代码,可以忽略不看。

    unit Unit16;
    
    interface
    
    uses
      Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes,
      Vcl.Graphics, Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls,System.Threading;
    
    type
      TFrame16 = class(TFrame)
        Label1: TLabel;
        Button1: TButton;
        Button2: TButton;
        procedure Button1Click(Sender: TObject);
        procedure Button2Click(Sender: TObject);
      private
        FTaskIsRunning:boolean;
        cnt:Integer;
      public
        { Public declarations }
      end;
    
    implementation
    
    {$R *.dfm}
    
    procedure TFrame16.Button1Click(Sender: TObject);
    begin
      FTaskIsRunning := true;
      TTask.Run(
        procedure
        begin
          while FTaskIsRunning do
          begin
            sleep(99);
            TThread.Synchronize(nil,
              procedure
              begin
                Label1.Caption := 'Thread is running...' + cnt.ToString;
                inc(cnt);
              end);
    
          end;
        end);
    end;
    
    procedure TFrame16.Button2Click(Sender: TObject);
    begin
      FTaskIsRunning := false;
      cnt := 0;
    end;
    
    end.

    然后,把Frame放到Form上运行,结果也正常。

    将上面的Frame+Form的实现方式,换成FMX项目,在Android,Win32平台运行,也正常。

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  • 原文地址:https://www.cnblogs.com/kinglandsoft/p/10367549.html
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