javascript - Why do companies rarely use node as the backend? Compared with the traditional backend of java, php, and python, what are the advantages of node and what is it suitable for?

Why do companies rarely use node as the backend? Compared with the traditional backend of java, php, and python, what are the advantages of node and what is it suitable for?

三叔 2017-06-28 09:23:09 0  1  1179

android - When starting the application, nothing is done in MainActivity and setcontent is not executed. Why is the memory occupied 25m?

When starting the application, nothing is done in MainActivity and setcontent is not executed. Why does the memory usage only reach 25m?

高洛峰 2017-05-16 13:32:41 0  1  550

Web crawler-Introduction to Python crawler

I am about to be a sophomore, I have studied Python by myself, and I know basic grammar. I want to learn crawling, but I feel that it involves a lot of knowledge. Is there anyone who has experienced it and can summarize what they know, or how to learn Python crawling?

欧阳克 2017-07-05 10:34:11 0  3  1198

redis - When running a python crawler, the MySQL version is 5.7 and an error is always reported

When running the python crawler, the MySQL version is 5.7 and an error is always reported {code...}. What is the problem? How to solve it?

扔个三星炸死你 2017-06-12 09:19:42 0  2  928

Python - The title of the web page contains a newline. How to extract it using regular expressions?

When using python as a web crawler for CSDN, when crawling the title of a web page, I always use the regular expression (?<=\<title\>).+?(?=\<) in CSDN No, I went to CSDN source code and took a look. The title was displayed in a new line, so the original regular expressio...

女神的闺蜜爱上我 2017-06-22 11:51:43 0  2  1004

python - How to check what kind of anti-crawler is used on a URL

URL: https://www.nvshens.com/g/22377/. Open the website directly with the browser and right-click on the image to download it. Then the image directly requested by my crawler has been blocked, and then I changed I have added headers and set up IP proxy, but it still doesn’t work. But if you look at ...

ringa_lee 2017-06-12 09:27:51 0  4  1289

How to import simple_HTML_DOM file in ThinkPHP5

I want to make a web crawler to obtain data. Now I have a simple_HTML_DOM.php file. How should I use it in TP5? Directly put the file content into common.php or how to use it?

NULL 2017-12-07 13:26:15 0  0  1207

Python - Faced with a string containing garbled characters, how to remove the required information

This is the train information that I saw based on the network on 12306. In order to prevent crawlers, he set up garbled codes. What should I do to find information such as train times from the garbled codes?

过去多啦不再A梦 2017-05-27 17:39:48 0  1  796

python - csdn crawler review

https://github.com/xchaoinfo/fuck-login/blob/master/015%20CSDN/csdn.py According to the comments on lines 87-88, why does it need to be converted into this link when using a crawler to comment on csdn articles? This How did you get the link? I looked at the web page code and there is no relevant lin...

仅有的幸福 2017-05-18 10:53:42 0  2  876

javascript - node crawls Weibo

I was new to node and wanted to write a crawler to crawl Sina Weibo comments, but I found that the page was dynamically generated by JS and could not be crawled using the http module, so I used phantomjs to crawl it (I heard it would be slower, and it took nearly a month to run) 15 minutes, this is ...

仅有的幸福 2017-06-30 10:00:08 0  1  999

python - scrapy crawls many more pages than actually enters items?

{Code...} Why do I visit more pages than actually enter items when I use scrapy to crawl? Is there any way to solve the problem that after crawling for a long time, there are not many pieces of data in the items?

PHP中文网 2017-05-18 10:47:40 0  1  671

python writes the xth column data to the xth file

The Python crawler needs to crawl a total of 65 pages of data, and the number of columns in each page of data is uncertain. Now I can capture the data of each column, but because the number of columns is uncertain, the file name written cannot be determined. The problem is how to write the x-th colu...

漂亮男人 2017-06-12 09:23:40 0  1  768

Can tp5.1 use auth for permission management???

When using auth to do permissions in tp5.1, an error is reported. What is the reason???

那个啥 2018-12-11 21:01:48 0  0  998

python - How to use a crawler to crawl images from web pages in batches?

As shown in the picture, it is troublesome to view and load pictures through the network and right-click to save them one by one. Is there any way to write a crawler to batch grab the pictures here?

给我你的怀抱 2017-06-28 09:25:48 0  3  1202

Web crawler - How to crawl the pictures in the Blog Park blog using python?

I wrote a small piece of code to crawl the pictures in the Blog Park blog. This code is effective for some links, but some links report errors as soon as they are crawled. What is the reason? {code...} As shown in the figure, the image can be crawled correctly. If the url is changed to {code...}, an...

某草草 2017-05-18 10:45:39 0  1  926

javascript - In addition to ajax, what else can be used to call the backend interface from the front end?

The company wants to build a mobile official website and cannot use ajax to call the interface (in order to capture data for others), so what else can be used? ? ? What does Baidu use to capture data?

仅有的幸福 2017-06-30 09:57:52 0  4  1167

javascript - When doing || operation between jquery objects, why is the returned value not of boolean type?

The jquery source code fragment is as follows: {Code...} I think the context here is a jquery object, and the rootjquery is $(document). But shouldn’t the demerits they return be a Boolean value? Why is it a jquery object here? So the || operation is in What is done here? What is his role??? Thank y...

漂亮男人 2017-05-16 13:35:57 0  2  528

Python crawls the data and gets a list, but how to remove the span tag in it?

I used p6ython3.6 to crawl some data, but what was finally displayed was a list containing span tags. When I used get_text, contents, etc., an error would be reported. Why is this? The initial result returned is as follows: {code...} My code is as follows: {code...}

我想大声告诉你 2017-05-18 10:55:53 0  3  1020

Why doesn't background filter work in React module CSS?

What am I doing wrong here? Why is the css not being applied to the div and making it blurry? Can anyone help make my navbar blurry? I want my navigation bar to be blurry

P粉590929392 2024-03-26 16:59:58 0  1  370

java - I encountered a problem while writing code today, that is, an object that was just saved into the session cannot be read out. I would like to ask what the problem is.

I made a login today and saved it with session in the background. I don’t know why I can’t get it and it’s still null. {code...}

大家讲道理 2017-06-10 09:48:02 0  1  746