Here you can find my private notes about programming that I wanted to share with you. Feel free to filter based on the topic you want or search for something specific.
How to fix the 'Unable to find "react" ("npm") in the registry' error when using the tool Typings and TypeScript
During the last years we see that every month new JavaScript frameworks/ tools/ libraries are comming out to the public and they all promise to help us develop better, faster and give more quality to our applications. One of the favorite combinations is currently the use of the React framework, TypeScript as superset of JavaScript and the webpack tool for combining files together, dependencies and more.
When using the combination, it is very probably that you are also going to use the Typings plugin for fast downloading of definitions files for TypeScript.
If you installed react with npm and you get the ‘Unable to find “react” (“npm”) in the registry’ error from Typings when you try to download the d.ts file of react, then here is the solution to your problem:
Create a breadcrumb list of links with JavaScript and use it inside your React applications!
The advantages of using breadcrumbs in your web applications are widely known.
The users get a chain of links that helps them understand where they are in your website and how they came to this page, and how provides them an easy when to navigate back in the hierarchy of links.
Breadcrumbs are considered to be a best practice for the SEO of your application.
Suppose we have the following example of chained links in a breadcrumb:
Main page > Main category 1 > Sub category 1 > Product 1
How to check if a string in JavaScript contains only numbers
There is often the case that you want to check if a string in JavaScript contains only numbers or you might just want to extract the numbers from a string, but you want to do this extraction only when the string only contains numbers. The most common case for such check is when you want to read a value (returned as string from JavaScript) from an input field of a form and evaluate if this value is a number or not.
How to convert a number in Less code into a valid CSS measuring unit
When working with less you most probably have to do some calculations and assign their result in a CSS property, for example into a width of a CSS class or a margin of an CSS id.
Apart from the calculated number you want to generate valid CSS code, so you also have to apply a measuring unit to this number, for example pixels or ems or percentages.