Python -- 网络编程 -- 简单抓取网页

抓取网页:　　urllib.request.urlopen(url).read().decode('utf-8')  ---  (百度是utf-8,谷歌不是utf-8，也不是cp936，ascii也不行，iso-8859-1勉强)

PyQt4.QtGui的QTextEdit控件自动解析HTML文档，为显示纯HTML文件，应使用方法QTextEdit.setPlainText()

例：抓取网页的标题、图片和链接

 import sys, re
 import urllib.request
 from PyQt4 import QtGui

 class MainWindow(QtGui.QWidget):
     def __init__(self):
         super(MainWindow, self).__init__()
         self.setWindowTitle('Crawl')
         self.resize(485, 300)

         self.txt = QtGui.QTextEdit()
 #         self.txt.setF
         self.txt.setReadOnly(True)

         grid = QtGui.QGridLayout()
         grid.addWidget(self.txt)
         self.setLayout(grid)

         url = 'http://www.baidu.com/s?wd=python'
         page = urllib.request.urlopen(url).read().decode('utf-8')
         fp = open('e:/temp.txt', 'wt', encoding='utf-8')
         fp.write(page)
         fp.close

         s = '标题：\n'
         page_title = re.compile('<title>(.+?)</title>')
         s += page_title.findall(page)[0]+'\n'

         s += '图片：\n'
         page_images = re.compile('<img src="(.+?)"')
         for data in page_images.findall(page):
             s += data+'\n'

         s += '链接：\n'
         page_link = re.compile('href="(.+?)"')
         for data in page_link.findall(page):
             s += data+'\n'

         self.txt.setPlainText(s)

 app = QtGui.QApplication(sys.argv)
 mainwindow = MainWindow()
 mainwindow.show()

 app.exec_()