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In node, many objects will launch events. For example, a TCP server emits a "connect" event whenever a client requests a connection, or, for example, whenever a whole piece of data is read, the file system emits a "data" event. These objects are

Encapsulation in JavaScriptencapsulation simply means that the outside world can only access the objects ' common variables and functions, hiding details and data.JS in three ways to create objects, respectively, for the portal open, with the naming

In JavaScript, you can use Try...catch for exception handling. For example: try { foo.bar (); } catch (e) { alert (e.name + ":" + e.message); } At present, we may get the system anomaly mainly contains the following 6 kinds: evalerror: Raised

1. What is read and write lock It is possible to allow multiple read threads to access at the same time, or locks that are blocked by all read threads and other write threads when the write thread is accessed. Read-write lock in two, divided into a

XML DOM support in IE IE support for XML is based on the MSXML library of ActiveX. 1. Dom Creation For each new version of MSXML, a different XML DOM object is created, so try to choose a new version of the XML DOM. 2. Loading XML Loading XML is

Javascript| Object | advanced First, write the constructorYou can use the new operator to combine predefined constructors such as Object (), Date (), and function () to create and initialize an object. The powerful feature of object-oriented

Demand: A, read a| in turn b| C three files and terminates immediately if there is a failure.B, simultaneous reading a| b| C three files and terminates immediately if there is a failure.First, callback 需求A： Let read = function (code) {if (code)

The MySQL log file is divided into 4 types: error log, universal query log, slow query log, and binary log.1. Error log: Log The problem that occurs when the MySQL server starts, runs, or stops.(1) Start and set error logThe error log feature is

 promise is a very simple concept, and even if you don't have a chance to use it, chances are that you've learned about it. Promise is a valuable constructor that can help you avoid using nested anonymous methods and assemble asynchronous code in a

Javascript| Object | advanced 　　First, write the constructor You can use the new operator to combine predefined constructors such as Object (), Date (), and function () to create and initialize an object. The powerful feature of object-oriented

Javascript| Advanced In program development, programmers often face how to write code to respond to the occurrence of error events, i.e. exception handling (exception handlers). If the exception-handling code is well-designed, then the final

In JavaScript, you can use Try...catch for exception handling. For example: Copy Code code as follows: try {foo.bar ();} catch (E) {alert (e.name + ":" + E.message);} At present, we may get the system anomaly mainly contains

Write the program in the morning, added a previous write a class, compile encountered the following error:... error C2061:syntax error:identifier ' This_file '.../new (+): Error c2091:function returns function.../new (+): Error C2809: ' operator new

This article mainly introduces the path ing (Routing) function and control of NodeJS framework express, which has some reference value. If you are interested, you can refer to it. This article mainly introduces the detailed description of NodeJS #

JS compression upload image JS compression upload Image /*** @ Date: 2016/11/17 0017 * @ Time: * @ Author: lxbin ** Created with JetBrains WebStorm .*//*** http://leonshi.com/2015/10/31/html5-canvas-image-compress-crop/ * http://jafeney.com/2016/08/

Common javascript error object processing, Error code set error object Property: Name: Error name Number: error number Description: description Message: error message, which is the same as description. FF Only attribute FileName: The file where the

The real problem with callback functions is that they deprive us of the ability to use the return and throw keywords. Promise solves all this well. Promise in js The real problem with callback functions is that they deprive us of the ability to

// Compare whether the array is the same as modeler. compArrayfunction (array1, array2) {if (array1 & amp; typeofarray1 & quot; object & quot; & amp; array1.constructorArray) & amp; (array2 & amp; & am // Compare whether the array is the sameModeler.

In the Chinese search, did not find a better about how to use their own pre-created database in the Android application of the article, so on Google to find this English article, according to its steps, test success, decided to translate this

For example, if the add method of a UserClass is successful, the user object instance is returned. If the instance fails, False is returned. You can use the getError method to obtain the string of the cause of failure ........ speaking of this, I