Android Official Database Room - Data Migration

Links to source documents data migration If app Adds / modifies feature s, it needs to redefine entity classes to reflect these changes. When the user updates, keep the original data, especially the data that cannot be recovered from the server. Room allows you to write Migration classes for data migration. Each Migration cl ...

Added by homchz on Sun, 19 May 2019 11:43:53 +0300

Java Web Base Disk - Other Articles

XML Operation of XML Files Conversion between XML and JavaBean 1. File operation 1)Create an empty XmlDoc XmlDoc doc = new XmlDoc(); 2)Use the external input element as the root element Element element = ... XmlDoc doc = new XmlDoc(element); 3)With the specified external file or xml Text string c ...

Added by bben95 on Sun, 19 May 2019 10:57:29 +0300

Front-end work series - ajax requests and cross-domain requests

Having been used to Ajax requests written by others, I suddenly want to write one myself. Because of this idea, I went to look up the information and finally figured out the steps of the original request for ajax. I would like to share with you here. If you want to make a request to the server, you must first have an o ...

Added by Drezek on Sun, 19 May 2019 09:45:44 +0300

Communication between Angular and Modal Box

When Angular is working on a project, it is inevitable to use a pop-up box (that is, a modal box). If there is a table in the modal box, the data in the table needs to be from the parent component (let's talk about it as a parent component for the time being). The data in the modal box table is modified and sent back to the parent component. Ho ...

Added by algy on Sun, 19 May 2019 08:35:03 +0300

Learning Js Basic Day 6 Objects and Built-in Objects Math,Date

Object-oriented What is the object? Something visible, tangible, specific Object Finding: Describing Object Finding Object: What are the characteristics of the object: characteristics and behavior Summarize what is the object Object: Something with characteristics and behavior, specific characteristi ...

Added by dunnsearch on Sun, 19 May 2019 03:00:41 +0300

Python Crawler Crawling Dynamic Page Ideas + Crawling Jingdong Example

brief introduction Sometimes, when we naively download HTML pages using urllib libraries or Scrapy, we find that the elements we want to extract are not in the HTML we download, although they seem to be readily available in browsers. This shows that the elements we want are dynamically generated through js events under some of our operations. F ...

Added by phast1 on Sat, 18 May 2019 10:14:26 +0300

Swagger Document to Word Document

GitHub address: https://github.com/JMCuixy/SwaggerToWord/tree/developer Original works, reproduced, please indicate the source: http://www.cnblogs.com/jmcui/p/8298823.html I. Preface Why does this demand arise? As Party B, our company is always chasing for an API document by customers, when we drop a Swagger document address to our customer ...

Added by Sassci on Sat, 18 May 2019 09:01:56 +0300

Node.js uses mongoose to manipulate mongodb

1. Software configuration: 1.node v8.9.3 2. npm 5.5.1 3. For the mongoose and MongoDB versions, see package.json below. // package.json { "name": "mongoosedemo", "version": "1.0.0", "description": "", "main": "index.js", "scripts": { "test": "echo \"Error: no test specified\" && exit 1" }, "autho ...

Added by chadt on Sat, 18 May 2019 07:37:48 +0300

Student information management system (data transmission between js and php)

The end of the latest period is approaching, busier, slower, forgive me. After setting up the environment and confirming the connection, we can start writing programs. Then build tables. insert data (Here's just one example) Also note when creating a table, because you want to create a view, you should build an ...

Added by Crow on Sat, 18 May 2019 05:36:08 +0300

Webpack 4 series of tutorials (15): development mode and webpack-dev-server

Author's Note: Because the pictures shown in the tutorial are github warehouse pictures, friends with slow network speed please move. "Webpack 4 series of tutorials (15): development mode and the original address of webpack-dev-server" . Welcome to my small station to see more original content: godbmw.com "Posture" communic ...

Added by Michiel on Fri, 17 May 2019 21:33:55 +0300