如何将JavaScript函数的结果放入python变量中.PyQt的

Question

我想在PyQt evaluateJavaScript()中创建一个函数(或者可能是类似函数),而不是显示求值函数的结果.实际功能会大得多,也可能不是字符串.

我只对如何在PyQt代码中创建函数以及将结果导入python变量感兴趣.

为了更清楚,我将举一个例子:这是我想loadFinished在http://jquery.com之后输入的js :

w = document.getElementsByTagName('p')[0];
w.innerHTML

如果我在浏览器控制台中执行此操作,我将获得输出:

"jQuery is a fast and concise JavaScript Library ...... blah blah blah"

我想将此输出存储在变量中.

#!/usr/bin/env python

from PyQt4.QtCore import *
from PyQt4.QtGui import *
from PyQt4.QtWebKit import *
import os, sys, signal
from urllib2 import urlopen

class GBot(QWebView):

    def __init__(self):
        QWebView.__init__(self)
        self.setPage(BrowserSettings())
        #self.jquery = get_jquery()
        self.load(QUrl('http://jquery.com'))
        self.frame = self.page().currentFrame()

    def _loadFinished(self, ok):
        doc = self.frame.documentElement()
        #doc.evaluateJavaScript(self.jquery)
        r = doc.evaluateJavaScript('''w = document.getElementsByTagName('p')[0]; w.innerHTML''')
        print r #want to do something like this


if __name__ == '__main__':
    app = QApplication(sys.argv)
    bot = GBot()
    bot.show()
    if signal.signal(signal.SIGINT, signal.SIG_DFL):
        sys.exit(app.exec_())
    app.exec_()

Answer 1

在这个例子中,我首先myWindow通过传递self到主框架来创建一个javascript对象,然后evaluateJavaScript在loadFinished以下情况下调用:

#!/usr/bin/env python
#-*- coding:utf-8 -*-

from PyQt4 import QtCore, QtGui, QtWebKit  

getJsValue = """ 
w = document.getElementsByTagName('p')[0];
myWindow.showMessage(w.innerHTML);
"""  

class myWindow(QtWebKit.QWebView):  
    def __init__(self, parent=None):
        super(myWindow, self).__init__(parent)

        self.page().mainFrame().addToJavaScriptWindowObject("myWindow", self)

        self.loadFinished.connect(self.on_loadFinished)

        self.load(QtCore.QUrl('http://jquery.com'))

    @QtCore.pyqtSlot(str)  
    def showMessage(self, message):
        print "Message from website:", message

    @QtCore.pyqtSlot()
    def on_loadFinished(self):
        self.page().mainFrame().evaluateJavaScript(getJsValue) 

if __name__ == "__main__":
    import sys

    app = QtGui.QApplication(sys.argv)
    app.setApplicationName('myWindow')

    main = myWindow()
    main.show()

    sys.exit(app.exec_())