JavaScript – Andreas Plahn Developer Blog

September 10, 2019September 10, 2019

npm- Specifying dependencies and devDependencies in a package.json file

Install packages required by your application in production:

npm install [package name]

Install packages that are only needed for local development and testing:

npm install [package name] --save-dev

NPM cheat sheet:
https://kapeli.com/cheat_sheets/npm.docset/Contents/Resources/Documents/index

Specifying dependencies and devDependencies in a package.json fileTo specify the packages your project depends on, you must list them as “dependencies” or “devDependencies” in your package’s package.json file. When you (or another user) run npm install, npm will download dependencies and devDependencies that are listed in package.json that meet the semantic version requirements listed for each. To see which versions of a package will be installed, use the semver calculator.”dependencies”: Packages required by your application in production.”devDependencies”: Packages that are only needed for local development and testing.

To specify the packages your project depends on, you must list them as "dependencies" or "devDependencies" in your package’s package.json file. When you (or another user) run npm install, npm will download dependencies and devDependencies that are listed in package.json that meet the semantic version requirements listed for each. To see which versions of a package will be installed, use the semver calculator.

"dependencies": Packages required by your application in production.
"devDependencies": Packages that are only needed for local development and testing.

Source: Specifying dependencies and devDependencies in a package.json file | npm Documentation

September 5, 2019

mockserver – npm

mockserver is a library that will help you mocking your APIs in a matter of seconds: you simply organize your mocked HTTP responses in a bunch of mock files and it will serve them like they were coming from a real API; in this way you can write your frontends without caring too much whether your backend is really ready or not.

Source: mockserver – npm

July 17, 2019July 17, 2019

Convert HTML + CSS to PDF. Print HTML in seconds

itnext.io/javascript-convert-html-css-to-pdf-print-supported-very-sharp-and-not-blurry-c5ffe441eb5e

April 3, 2019

How to Update npm Packages to their Latest Version – HostingAdvice.com

Source: How to Update npm Packages to their Latest Version – HostingAdvice.com

March 21, 2019

Javascript debugging helper – Count number of eventlisteners in Chrome console

Paste and run one of the code blocks below in chrome console to get eventlisteners count.

//eventlisteners counter - grouped summary

Array.from(document.querySelectorAll('*')) .reduce(function(pre, dom){

var evtObj = getEventListeners(dom)

Object.keys(evtObj).forEach(function (evt) {

if (typeof pre[evt] === 'undefined') {

pre[evt] = 0

}

pre[evt] += evtObj[evt].length

})

return pre

}, {})

//_-------------------------------------------

// //eventlisteners - totalcount

var totalCount = 0;

Array.from(document.querySelectorAll('*')).reduce(function(pre, dom){

var evtObj = getEventListeners(dom)

Object.keys(evtObj).forEach(function (evt) {

if (typeof pre[evt] === 'undefined') {

pre[evt] = 0

}

// pre[evt] += evtObj[evt].length

totalCount += evtObj[evt].length;

})

return totalCount;

}, {})

//---------------------------------------

March 15, 2019March 15, 2019

jasmine parameterized unit test – Stack Overflow

Based on piotrek’s answer and the article Parameterized testing in Javascript, you could also use the following approach which uses ES6 syntax:

JavaScript

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[
['abc', 3],
['ab', 2],
['', 0],
].forEach(([string, expectedLength]) => {
it(`should return length ${expectedLength} for string "${string}"`,
() => { expect(string.length).toBe(expectedLength); });
});

I have tested it with the Jest test framework, but it should work with Jasmine as well.

Source: jasmine parameterized unit test – Stack Overflow

March 8, 2019

How to use underscore lib from DefinitelyTyped with typescript? – Stack Overflow

Step 1. install type definitions (e.g. vs code intellisense) to project:
npm install –save @types/underscore

(https://www.npmjs.com/package/@types/underscore)

Step 2. import to ts file:

import * as _ from “underscore”;

Source: How to use underscore lib from DefinitelyTyped with typescript? – Stack Overflow

February 27, 2019

TypeScript vs. C#: LINQ

TypeScript counterparts for C# LINQ.

Source: TypeScript vs. C#: LINQ

January 8, 2019January 8, 2019

How to include and use jQuery in Angular CLI project

Tested in angular version 7:

install jquery:
npm install jquery
install jquery typescript intellisense:
npm install @types/jquery
edit the angular.json file in root folder:
in the architect / build / scripts location, add this:

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"scripts": [ "./node_modules/jquery/dist/jquery.min.js" ]
To use jquery inside a component.ts add this import at the top:

import $ from ‘jquery’;

Example code to check for functionality:
component html:

XHTML

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<button (click)="testJQuery()">Test jquery</button>

component.ts:

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testJQuery() {
$('html').fadeOut();
$('html').fadeIn();
}

Click on the button should fade out and fade in the entire page.

Source: How to include and use jQuery in Angular CLI project

December 31, 2018

json2typescript – npm

NPM Package for converting from JSON to TypeScript object.

json2typescript In Angular 2 applications, everyone consumes JSON API’s from an external source. Type checking and object mapping is only possible in TypeScript, but not in the JavaScript runtime. As the API may change at any point, it is important for larger projects to verify the consumed data. json2typescript is a small package containing a helper class that maps JSON objects to an instance of a TypeScript class. After compiling to JavaScript, the result will still be an instance of this class. One big advantage of this approach is, that you can also use methods of this class.

Source: json2typescript – npm