Whenever a DOM element changes, we can capture it using MutationObserver. Basically you can create a new MutationObserver(callback) instance and then invoke the observe(targetNode, config) function.
On a recent project there was a shop plugin I was using in a cart page. Every time user updated quantity, the form element’s id was changing randomly and I did not know how to access its reference.
In a situation like this, you can add a parent element to that <form> and observe that parent element for mutation changes....
Imported and tried to use the Switch as in the following;
import { Switch, Route } from 'react-router-dom' class App extends React.Component { ... ... render() { return ( .... <Switch> <Route exact ...> <Switch> .... ) } } But it threw the error mentioned in the title. Looks like the project has some breaking changes starting from v6.x
So, either you update <Switch /> elements to <Routes />, for details have a look this link, or you can just rollback the react-router-dom version to the latest v5 which currently is v5....
We happen to guess that the this keyword’s usage is same to the ones in Java or C# or any other OOP language. But it’s not true. I’ve been following the book series You Don’t Know JS, and i gotta say using this is not that easy as it looks.
What We Normally Assume We think that it refers to the function that it resides in. For example think about this C# code:...
Let’s say you want to do write numbers from 0 to 10 in a for loop, but you want this to happen after a certain amount of time. Let’s do this the old way we know
Using var keyword I guess that you’d come up with a solution like this:
var counter = 10; for(var i = 0; i < counter; i++){ setTimeout(function timer(){ console.log(i); },1000); } The above code should write the numbers in 1 seconds break, but the ouput is not as we expected, it should write 10 ten times....
This is a simple Tic Tac Toe game written in Angular 2. You can find the source code here
Root Component The project is again generated by angular-cli. I did not include routing in the app. There is only a root component and an HTML & CSS file for it. I also did not touch index.html
Logic Let’s have a look at our component, navigate to src/app/app.component.ts.
We have predefined some of our data and also we have this constructor:...