node js console log

3.1 Console/19 in node. js3.1.1 Console.log method/193.1.2 Console.error Method/203.1.3 Console.dir Method/213.1.4 Console.time Method and Console.timeend method/223.1.5 Console.trace Method/223.1.6 Console.assert Method/233.2 Global scope and global functions in node. js/233.2.1 Global scope/23 in

start position of File Reading. If this parameter is set to null, data is read from the current file pointer. The callback passes three parameters: err, bytesRead, and buffer. · Err exception · BytesRead: number of bytes read · Buffer: buffer object Example: The Code is as follows: Var fs = require ('fs ');Fs.open('123.txt ', 'R', function (err, fd ){If (err ){Console. error (err );Return;} Var buf = new Buffer (8 );Fs. read (fd, buf, 0, 8, null, f

This article mainly introduces Node. this article describes how to use some open-source libraries to solve the garbled problem during crawling. For more information, see Node. garbled characters may occur when JavaScript captures a non-UTF-8 Chinese webpage. for example, if NetEase's homepage code is gb2312, garbled characters may occur during crawling. The code is as follows: Var request = require ('requ

Talking about node. js database Exception Handling, talking about node. js Exception Handling This article describes how to handle node. js database exceptions: NodeJs version: 4.4.4 Database Link error It is the most troublesome

Recently written program node. data storage is required for js programs. there are many databases that js can use, such as mongodb and MySQL. However, I still think these databases are too large to be useful, making them more troublesome. So I found node-tiny, a non-relational database, a bit similar to mongodb.Tiny's

, index) {return new Promise (function (resolve, reject) {fs. readFile (file, 'utf-8', function (err, str) {if (! Err) {resolve (str)} else {reject (err) }}) ;}); return Promise. all (readFilsePromiseList );}). then (function (fileStrArray) {console. log ('after reading the so-called file: '+ fileStrArray );}); This Code indeed shows the elegance of nodejs development. So where is the problem? Currently, th

This article mainly introduces node. socket. io broadcast messages. For more information, see socket. the io () server has a sockets attribute. The attribute value is all socket objects connected to the client. you can use the send method or emit method of this object to broadcast messages to all clients. Io. sockets. send ("user commected ); Io. socket. emit ("login", names ); Case Server. js code: The

This article mainly introduces node. url in js. description of the parse method. This article describes the url. parse method description, syntax, receive parameters, use instances, and implement Source Code. For more information, see Method description: Converts a URL string to an object and returns it. Syntax: The Code is as follows: Url. parse (urlStr, [parseQueryString], [slashesDenoteHost]) Receivi

This article mainly introduces node. url in js. the format method is described in this document. format method description, syntax, receive parameters, use instances, and implement Source Code. For more information, see Method description: Convert a parsed URL object into a formatted URL string. Syntax: The Code is as follows: Url. format (urlObj) Receiving parameters: UrlObj indicates a URL object and

This article mainly introduces how to use socket in node. for more information about how to create a namespace for I/O, see. If a developer wants to completely control the sending of messages and events in a specific application, you only need to use a default "/" namespace. however, if developers need to provide applications to other applications as third-party services, they need to define an independent namespace for a socket port used to connect t

Example of Node. js readline Reading and Writing File Content line by line, node. jsreadline This article describes the two implementation methods of reading data row by row using readline. The details are as follows: What is Readline? Readline is an encapsulated module for implementing standard input and output in Node