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 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.
Is there a naming convention for TypeScript interfaces?
The TypeScript language was created from Microsoft as a super-set of typed-rules for JavaScript. The language contains features that one finds in C#, something that is completely understandable since the inventor of TypeScript also invented C#.
TypeScript provides interfaces that are used for two main reasons:
Standardize/ Giving a type to an object, by defining the properties that an object contains.
Define a structure of properties and/ or functions that a class has to implement. Doing this way you can define multiple implementations that implement the interface. In this case, the interface works as a contract (known best practice term from C#) that the classes have to respect.
Five common error messages in Angular.js and how to quickly solve them
When using Angular.js and something goes wrong with your code, the first place to look for an error message that came from your JavaScript code is in the console of the browser debugger that you use (for example Chrome developer tools or IE F12).
In the following list you see a collection of common error messages that you will most probably come along when you implement web application with Angular.js. Together with each message you see a quick solution to fix your code: