Java Script
JavaScript (not to be confused with Java) is a high-level, dynamic, multi-paradigm, weakly-typed language used for both client-side and server-side scripting. Its primary use is in rendering and allowing manipulation of web pages. Use this tag for questions regarding ECMAScript and its various dialects/implementations (excluding ActionScript and Google-Apps-Script).
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How to get first N number of elements from an array
I am working with Javascript(ES6) /FaceBook react and trying to get the first 3 elements of an array that vari
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Difference between npx and npm?
I have just started learning React, and Facebook helps in simplifying the initial setup by providing the follo
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How to set focus on an input field after rendering?
What's the react way of setting focus on a particular text field after the component is rendered? Docume
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How do I conditionally add attributes to React components?
Is there a way to only add attributes to a React component if a certain condition is met? I'm supposed to
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React js onClick can't pass value to method
I want to read the onClick event value properties. But when I click on it, I see something like this on the co
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Why do we need middleware for async flow in Redux?
According to the docs, "Without middleware, Redux store only supports synchronous data flow". I don't und
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Understanding unique keys for array children in React.js
I'm building a React component that accepts a JSON data source and creates a sortable table. Each of the
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React-router urls don't work when refreshing or writing manually
I'm using React-router and it works fine while I'm clicking on link buttons, but when I refresh my w
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How to pass props to {this.props.children}
I'm trying to find the proper way to define some components which could be used in a generic way: <Pa
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What does the three dots notation do in Javascript?
What does the ... do in this React (using JSX) code and what is it called? <Modal {...this.props} title=&a
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Loop inside React JSX
I'm trying to do something like the following in React JSX (where ObjectRow is a separate component): <
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How can I print a circular structure in a JSON-like format?
I have a big object I want to convert to JSON and send. However it has circular structure. I want to toss what
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How do I convert an existing callback API to promises?
I want to work with promises but I have a callback API in a format like: 1. DOM load or other one time event:
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module.exports vs exports in Node.js
I've found the following contract in a Node.js module: module.exports = exports = nano = function databas
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How to access POST form fields
Here is my simple form: <form id="loginformA" action="userlogin" method="post"> <div>
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Error: Can't set headers after they are sent to the client
I'm fairly new to Node.js and I am having some issues. I am using Node.js 4.10 and Express 2.4.3. When
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Sending command line arguments to npm script
The scripts portion of my package.json currently looks like this: "scripts": { "start": "node ./script.js
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25
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In Node.js, how do I "include" functions from my other files?
Let's say I have a file called app.js. Pretty simple: var express = require('express'); var ap
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Using Node.js require vs. ES6 import/export
In a project I'm collaborating on, we have two choices on which module system we can use: Importing modu