Programming Articles - Page 1220 of 3363

NodeJS is a JavaScript runtime environment that was built on top of Chrome's V8 engine. The traditional use of JavaScript is to be executed in browsers, but with Node.JS we can execute JavaScript other than browsers like servers, hardware devices, etc.process.cwd()The process object lies under the global object known as 'global'. This method provides information about the current process of Node.js. It also provides control over the same. cwd refers to the current working directory of the same. Therefore, process.cwd returns the working directory on which execution is taking place currently.__dirnameThis is a local module that will return the directory ... Read More

Both the methods – console.log and process.stdout.write have a basic definition to write or print the statements on the console. But, there is a slight difference in the way they execute these tasks. Internally, console.log implements process.stdout.write which itself is a buffer stream that will be used to directly print statements on your console.process.stdout.writeconsole.logIt continuously prints information as retrieved from the stream without adding any new line.It first prints the information being retrieved and then adds a new line. Then it will go to retrieve the second set of statements to print.The process.stdout.write method takes only string as paramter. Other ... Read More

Introduction to SequelizeSequealize follows the promise-based Node.js ORM for different servers like – Postgres, MySQL, MariaDB, SQLite, and Microsoft SQL Server.Following are some of the main features of NodeJS sequelize −Transaction SupportRelationsEager and Lazy LoadingRead Replication and more...Connecting to MySQL using SequelizeWe need to establish a connection between MySQL and Node.js using Sequelize.After creating a successful connection with sequelize, we would require the following three files for configuration. Please carefully create the following files in their respective folders only.SequelizeDemo > application.jsThis will be our root file which will hold the actual logic.SequelizeDemo>utils>database.jsThis will hold all the connection details to MySQL.SequelizeDemo>models>user.jsThis ... Read More

Introduction to mongodb.connectThis method is used to connect the Mongo DB server with our Node application. This is an asynchronous method from MongoDB module.Syntaxmongodb.connect(path[, callback])Parameters•path – The server path where the MongoDB server is actually running along with its port.•callback – This function will give a callback if any error occurs.Installing Mongo-DBBefore proceeding to try connect your application with Nodejs, we need to setup our MongoDB server first.Use the following query to install mongoDB from npm.npm install mongodb –saveRun the following command to set up your mongoDB on the specific localhost server. This will help in creating connection with the ... Read More

Introduction to Async copyThis method copies files or directories from one location to another location. The directory can have sub-directories and files.Syntaxcopy(src, dest[, options][, callback])Parameterssrc – This is a string paramter which will hold the source location of the file or directory that needs to be copies. If the location is a directory, it will copy everything inside of the directory instead of whole directory.dest – This will hold the destination location where the files/directories will be copies. If src is a files, dest cannot be a directory.options −overwrite – If set to true, existing files or directories will be ... Read More

The most basic difference between cohesion and coupling is that coupling is the representation of relationships between modules which uses the concept of inter−module, while cohesion is the intramodule representation of the relationship between modules. Read this article to find out more about Cohesion and Coupling and how these two important concepts are different from each other. What is Cohesion? In computer programming, cohesion is an indication that shows the relationship within modules. Cohesion provides the information about the functional strength of the modules. The greater the cohesion, the better will be the program design. Cohesion is basically the dependency ... Read More

In this post, we will understand the difference between PLA and PAL −PLAIt stands for Programmable Logic Array.Its speed is lesser in comparison to PAL.It is highly complex.It is expensive.It is not available easily.It is used less in comparison to PAL.PALIt stands for Programmable Array Logic.It has a higher speed in comparison to PLA.It is less complex.It is inexpensive.It is more readily available in comparison to PLA.It is used more in comparison to PLA.

In order to work with a tkinter application, we have to install and import the tkinter library in our environment. Generally, we import the tkinter library in the environment by using from tkinter import * command.The significance of "import *" represents all the functions and built-in modules in the tkinter library. By importing all the functions and methods, we can use the inbuilt functions or methods in a particular application without importing them implicitly.There are lots of widgets, functions, methods available in tkinter library which can be used to construct the component of a particular application. Tkinter provides the ttk ... Read More

Tkinter is a Python package which comes with many functions and methods that can be used to create an application. In order to create a tkinter application, we generally create an instance of tkinter frame, i.e., Tk(). It helps to display the root window and manages all the other components of the tkinter application. We can initialize the tkinter instance by assigning the variable to it.ExampleIn the following example, we will create an instance of tkinter frame and create a label widget.#Import tkinter library from tkinter import * #Create an instance of tkinter frame or window win= Tk() #Set the ... Read More

Tkinter variable (var) is defined for a particular widget (textvariable=var) to store the updated value of a widget. Sometimes, there might be a case, while updating the variable information, we need to process some extra operations such as read, write, or undefined.Tkinter provides a way to update the variable with a callback function trace (self, mode, callback) which takes the operation of the process such as read(r), write(w), or undefined(u). On the basis of these values, the callback decides what the process needs to do in the callback function. The other two values define the variable which needs to be ... Read More