python web crawler code

Python is a powerful computer programming language. It can also be seen as an object-oriented general language. It has outstanding features and greatly facilitates the application of developers. Here, let's take a look at the Python city and county web crawler methods. Today, I saw a webpage, and it was very troublesom

) print imglist cnt = 1 for Imgurl in imglist: urllib.urlretrieve (Imgurl, '%s.jpg '%cnt) cnt + 1if __name__ = = ' __main__ ': html = gethtml (' http://www.baidu.com ') getimg (HTML) According to the above method, we can crawl a certain page, and then extract the data we need. In fact, we use urllib this module to do web crawler efficiency is extremely low, let us introduce Tornado

download and save the picture. Open the file as follows. The next step is to start identifying the verification code in the image, which requires the Pytesser and pil libraries. The first is to install TESSERACT-OCR and install it after downloading it online. The default installation path is C:\Program FILES\TESSERACT-OCR. Add the path to the system property's path path. Then install pytesseract and PIL via Pip . Let's see how it's used. The

1, Python code, such as, we fromhttp://gitbook.cn/Crawl data in this site.2, before running the code to download the installation of Chardet and requests installation package, you can download the two installation packages in my blog for free. Unzip and place in the directory where Python is installed, such as3. Open t

The code and tools usedSample site source + Framework + book pdf+ Chapter codeLink: https://pan.baidu.com/s/1miHjIYk Password: af35Environmentpython2.7Win7x64Sample Site SetupWswp-places.zip in the book site source codeFrames used by the Web2py_src.zip site1 Decompression Web2py_src.zip2 then go to the Web2py/applications directory3 Extract the Wswp-places.zip to the applications directory4 return to the previous level directory, to the Web2py directo

Project tutorial/: The project's Python module, which will reference the code from here tutorial/items.py: Project Items file tutorial/pipelines.py: Project's Pipelines file tutorial/settings.py: Setup file for Project tutorial/spiders/: Directory for crawler storage 2. Clear Target (Item) In Scrapy, items is a container for loading crawling

The crawler simply says it consists of two steps: Get the Web page text, filter the data. 　　 1. Get HTML text.Python is very handy for getting HTML, and just a few lines of code can do what we need. The code is as follows: def gethtml (URL):page = Urllib.urlopen (URL)html = Page.read ()Page.close ()return HTML Such

# Python3 Import Request Package from Urllib ImportRequestImport SYSImport io# If you need print printing, you can set the output environment first if an exception occursSys.StdOut=Io.Textiowrapper (SYS.StdOut.Buffer, encoding=' Utf-8 ')# The URL you need to getUrl= ' http://www.xxx.com/'# header FileHeaders={"User-agent":"mozilla/5.0 (Windows NT 10.0; WOW64) applewebkit/537.36 (khtml, like Gecko) chrome/64.0.3282.186 safari/537.36 "}# Generate Request ObjectReq=Request.Request (URL, headers=Hea

The reptile simply includes two steps: getting the Web page text, filtering the data. 　　 1, get the HTML text.Python is handy for getting HTML, and a few lines of code can do what we need. Copy Code code as follows: def gethtml (URL): page = Urllib.urlopen (URL) html = Page.read () Page.close ()

just a webpage introduction. Next, let's look at a novel interface: Below is the novel of the fast reading network, the novel text on the left, and the relevant webpage code on the right. No. The text of all novels is contained in the elements whose tags are If we have a tool, we can automatically download the corresponding HTML code elements. You can automatically download the novel. This is the

crawling around the web.Web spiders are looking for Web pages through the URL of a Web page.From one page of the site (usually the homepage), read the contents of the Web page, find the other links in the Web page, and then find the next page through these links, so that the cycle continues until all the pages of this

[Python] web crawler (6): A simple example code of Baidu Post bar crawlers. For more information, see. [Python] web crawler (6): a simple web