python - 如何在分离模式下终止进程

Question

我使用 PyQt5 在 Python 3.8 中开发应用程序。

我需要运行并能够从 PyQT 表单中终止一个单独的进程。当我使用 process.start 然后使用 process.kill 时，它会终止该进程。

但是当我使用 process.startDetached() 时，process.kill() 不起作用。

下面是一个例子:

from form import Ui_MainWindow
from PyQt5 import QtWidgets

class myapp(QtWidgets.QMainWindow):

    def __init__(self):
        super(myapp, self).__init__()
        self.ui = Ui_MainWindow()
        self.ui.setupUi(self)
        self.process = QProcess(self)
        self.ui.pushButton.clicked.connect(self.btnClicked)
        self.ui.pushButton_2.clicked.connect(self.process.kill)

    def btnClicked(self):
        runstr = 'ping'
        args = ['localhost','-t']
        self.process.startDetached(runstr, args)

app = QtWidgets.QApplication([])
application = myapp()
application.show()
sys.exit(app.exec())

您能否建议如何在分离模式下终止进程。

Answer 1

当您启动分离进程时，QProcess 无法终止该进程，因此在这些情况下，您必须获取子进程的 pid 并使用操作系统方法来终止它，如以下问题的答案所示:

• How to terminate process from Python using pid?
• Is it possible to kill a process on Windows from within Python?

from PyQt5 import QtCore, QtWidgets

import psutil

from form import Ui_MainWindow


class MyApp(QtWidgets.QMainWindow):
    def __init__(self, parent=None):
        super(MyApp, self).__init__(parent)
        self.ui = Ui_MainWindow()
        self.ui.setupUi(self)
        self.process = QtCore.QProcess(self)
        self.ui.pushButton.clicked.connect(self.start_process)
        self.ui.pushButton_2.clicked.connect(self.stop_process)
        self._pid = -1

    @QtCore.pyqtSlot()
    def start_process(self):
        runstr = "ping"
        args = ["localhost", "-t"]
        self.process.setProgram(runstr)
        self.process.setArguments(args)
        ok, pid = self.process.startDetached()
        if ok:
            self._pid = pid

    @QtCore.pyqtSlot()
    def stop_process(self):
        if self._pid > 0:
            p = psutil.Process(self._pid)
            p.terminate()
            self._pid = -1


if __name__ == "__main__":

    import sys

    app = QtWidgets.QApplication(sys.argv)
    application = MyApp()
    application.show()
    sys.exit(app.exec_())