React.memo to memoize the function component, but there is a second argument that is not used very often (and that you may not want to use for reasons discussed below). I have the opportunity to use a second argument of React.memo several times these days. Therefore, I note this article. What is the second argument of React.memo ? …

componentDidUpdate is the function calldeafter some values are updated in setState. Advantages You can get th value after the update most safety. You can pick the value up before the update. It doesn’t make user unconfortable even if setState doesn’t have extra drawing in componentDidUpdate. Basic Usage componentDidUpdate(prevState) { if (this.state.name !==…

What are Generics? First of all, languages like C# and Java also have generics, so it’s not limited to TypeScript. Generics which abstract type arguments use are used to implement classes, functions, and interfaces that types are not determined until they are actually used. Advantages of Generics Programming languages such as Java, C…

tips Use JSX.Element, React.ReactNode, etc. for the specified Props type. When it receives the components, receive props as an argument and extract the component from props. When creating a function component, props are often written as ({child1, child2}) etc. in the argument, but it should be (props) (probably because of rendering). Code Suppose a components called Children receives the components with props names child1 and child2.

“How many pixels should the margin here be ?” When designing WEB and UI, I often thought like this. I came to one conclusion after a bunch of research. That is, “make the margin a multiple of 8”. Benefits of making margin a multiple of 8 Many screen sizes are divisible by 8.

There are many talks about the goodness of GraphQL, but I think that the question “How do you actually implement it in Go?” Can not be understood unless you move it by hand with a brief Get Started of gqlgen. …

I tried to add GitHub Actions to my personally developed app and built a CI / CD environment. It was my first time to touch CI / CD . I hope it helps. Introduced GitHub Actions Create .github/workflows/main.yml (filename is arbitrary) in the root directory. Basically, just upload this configuration file (main.yml) …

Benefits of building an environment Coding rules can be tightened in team production etc. -> If each team does their own coding, no one can read would be completed. Eliminate the weird habits of coding from beginners -> If you have a strange habit from a beginner, it is difficult to correct it. Eliminate coding…

Web application created with React is containerized with docker and started. In this article, all I do is add docker-compose.yml to my already created app. If you do not have your own react project (with Typescript), you can make your react project according to here. The folder strucure is like: …