Once created, these custom elements -- a custom counter, for example -- can also be used in other single-page application (SPA) web frameworks such as React and Angular. A sample project, aptly titled Blazor Custom Elements, shows how to do just that, providing examples about how to work with those frameworks and the client-side Blazor WebAssembly component as well as Blazor Server.
Component architectures are an important part of ever modern front-end framework. In this article, I’m going to dissect Polymer, React, Rio.js, Vue.js, Aurelia and Angular 2 components. The goal is to make the commonalities between each solution obvious. Hopefully, this will convince you that learning one or the other isn’t all that complex, given that everyone has somewhat settled on a component architecture.
Sad news from the folks behind Firefox — they've laid off a quarter of their entire workforce, which reportedly includes both the DevTools and MDN teams.
Project Reunion: An End to Microsoft’s UI Madness?
JavaScript is a language written for websites to run in the client’s browser.
AJAX is a way for JavaScript to request data from a server without refreshing the page or blocking the application.
jQuery is a JavaScript library built to automate and simplify common web tasks like AJAX or animation.
Angular is a hip JavaScript framework which is made for building large, single-page web applications.
Node.js allows JavaScript to be run without a browser, and is commonly used to run web servers.
A draft of the release notes for Mono 4.0 have been posted. Among other changes, they have started to adopt code from Microsoft’s CoreCLR project.
import { decorate } from "mobx";
class Count {
value = 0;
}
decorate(Count, { value: observable });
const count = new Count(); const text = observable({
value: "Hello world!",
get uppercase() {
return this.value.toUpperCase();
}
}); > create-react-app state-management-with-mobx-part3 > cd state-management-with-mobx-part3 > npm start
> npm install --save mobx
<!DOCTYPE html>
<html lang="en">
<head>
<title>MobX Basics, part 3</title>
<meta charset="UTF-8" />
<link href="src/styles.css" />
</head>
<body>
<main>
<input id="text-input" />
<p id="text-display"></p>
<p id="text-display-uppercase"></p>
</main>
<script src="src/index.js"></script>
</body>
</html> import { autorun, computed, observable } from "mobx";
const input = document.getElementById("text-input");
const textDisplay = document.getElementById("text-display");
const loudDisplay = document.getElementById("text-display-uppercase");
class Text {
@observable value = "Hello World";
@computed get uppercase() {
return this.value.toUpperCase();
}
}
const text = new Text();
input.addEventListener("keyup", event => {
text.value = event.target.value;
});
autorun(() => {
input.value = text.value;
textDisplay.textContent = text.value;
loudDisplay.textContent = text.uppercase;
}); ./src/index.js
SyntaxError: \src\index.js: Support for the experimental syntax 'decorators-legacy' isn't currently enabled (8:3):
6 |
7 | class Text {
> 8 | @observable value = "Hello World";
| ^
9 | @computed get uppercase() {
10 | return this.value.toUpperCase();
11 | } import { observable, computed, action } from "mobx";
class Timer {
@observable start = Date.now();
@observable current = Date.now();
@computed
get elapsedTime() {
return this.current - this.start + "milliseconds";
}
@action
tick() {
this.current = Date.now();
}
} import { observable, computed, action, decorate } from "mobx";
class Timer {
start = Date.now();
current = Date.now();
get elapsedTime() {
return this.current - this.start + "milliseconds";
}
tick() {
this.current = Date.now();
}
}
decorate(Timer, {
start: observable,
current: observable,
elapsedTime: computed,
tick: action
}); const Counter = observer(({ count }) => {
return (
// ...
);
}); > create-react-app my-proj1 --typescript
{
"compilerOptions": {
// ...
"experimentalDecorators": true
}
} > npm i --save-dev customize-cra react-app-rewired
const {
override,
addDecoratorsLegacy,
disableEsLint
} = require("customize-cra");
module.exports = override(
// enable legacy decorators babel plugin
addDecoratorsLegacy(),
// disable eslint in webpack
disableEsLint()
); "scripts": {
"start": "react-app-rewired start",
"build": "react-app-rewired build",
"test": "react-app-rewired test",
"eject": "react-app-rewired eject"
}, {
"extends": "react-app",
"parserOptions": {
"ecmaFeatures": {
"legacyDecorators": true
}
}
} {
"env": {
"node": true,
"commonjs": true,
"browser": true,
"es6": true,
"mocha": true
},
"settings": {
"react": {
"version": "detect"
}
},
"parserOptions": {
"ecmaFeatures": {
"jsx": true,
"legacyDecorators": true
},
"ecmaVersion": 2018,
"sourceType": "module"
},
"plugins": [
"babel",
"react",
"react-hooks",
"react-redux",
"no-async-without-await",
"css-modules",
"filenames",
"simple-import-sort"
],
"rules": {
"no-const-assign": "warn",
"no-this-before-super": "warn",
"constructor-super": "warn",
"strict": [
"error",
"safe"
],
"no-debugger": "error",
"brace-style": [
"error",
"1tbs",
{
"allowSingleLine": true
}
],
"no-trailing-spaces": "error",
"keyword-spacing": "error",
"space-before-function-paren": [
"error",
"never"
],
"spaced-comment": [
"error",
"always"
],
"vars-on-top": "error",
"no-undef": "error",
"no-undefined": "warn",
"comma-dangle": [
"error",
"never"
],
"quotes": [
"error",
"double"
],
"semi": [
"error",
"always"
],
"guard-for-in": "error",
"no-eval": "error",
"no-with": "error",
"valid-typeof": "error",
"no-unused-vars": "error",
"no-continue": "warn",
"no-extra-semi": "warn",
"no-unreachable": "warn",
"no-unused-expressions": "warn",
"max-len": [
"warn",
80,
4
],
"react/prefer-es6-class": "warn",
"react/jsx-boolean-value": "warn",
"react-hooks/rules-of-hooks": "error",
"react-hooks/exhaustive-deps": "warn",
"react/prop-types": "off",
"react-redux/mapDispatchToProps-returns-object": "off",
"react-redux/prefer-separate-component-file": "off",
"no-async-without-await/no-async-without-await": "warn",
"css-modules/no-undef-class": "off",
"filenames/match-regex": [
"off",
"^[a-zA-Z]+\\.*\\b(typescript|module|locale|validate|test|action|api|reducer|saga)?\\b$",
true
],
"filenames/match-exported": "off",
"filenames/no-index": "off",
"simple-import-sort/sort": "error"
},
"extends": [
"react-app",
"eslint:recommended",
"plugin:react/recommended",
"plugin:react-redux/recommended",
"plugin:css-modules/recommended"
],
"globals": {
"Atomics": "readonly",
"SharedArrayBuffer": "readonly",
"process": true
}
} >npm i --save-dev eslint babel-eslint eslint-config-react-app eslint-loader eslint-plugin-babel eslint-plugin-react eslint-plugin-css-modules eslint-plugin-filenames eslint-plugin-flowtype eslint-plugin-import eslint-plugin-no-async-without-await eslint-plugin-react-hooks eslint-plugin-react-redux eslint-plugin-redux-saga eslint-plugin-simple-import-sort eslint-loader typescript
const {
override,
addDecoratorsLegacy,
useEslintRc
} = require("customize-cra");
module.exports = override(
addDecoratorsLegacy(),
useEslintRc(".eslintrc.json")
); Experimental support for decorators is a feature that is subject to change in a future release. Set the 'experimentalDecorators' option in your 'tsconfig' or 'jsconfig' to remove this warning.ts(1219)
{
"compilerOptions": {
"experimentalDecorators": true,
"allowJs": true
}
} Developed by Microsoft’s Research in Software Engineering, Code Contracts provide a way to convey code assumptions in your .NET applications. They can take the form of preconditions, postconditions, and state invariants. In C# Code Contracts Succinctly, author Dirk Strauss demonstrates how to use Code Contracts to validate logical correctness in code, how they can be integrated with abstract classes and interfaces, and even how they can be used to make writing documentation less painful.
