I feel like none of the answers have crystallized why mapDispatchToProps is useful. This can really only be answered in the context of the container-component pattern, which I found best understood by first reading:Container Components then Usage with React. In a nutshell, your components are supposed to be concerned only with displaying stuff. The only place they are supposed to get information from is … Read more
You should avoid using refs, you can do it with onChange function. On every change, update the state for the changed field. Then you can easily check if that field is empty or whatever else you want. You could do something as follows : In this example I did the validation only for email and name, but … Read more
First of all wrap the src in {} Then if using Webpack; Instead of: <img src={“./logo.jpeg”} /> You may need to use require: <img src={require(‘./logo.jpeg’)} /> Another option would be to first import the image as such: import logo from ‘./logo.jpeg’; // with import or … const logo = require(‘./logo.jpeg); // with require then plug it in… … Read more
componentWillReceiveProps is required if you want to update the state values with new props values, this method will get called whenever any change happens to props values. In your case why you need this componentWillReceiveProps method? Because you are storing the props values in state variable, and using it like this: this.state.KeyName That’s why you … Read more
NPM – Manages packages but doesn’t make life easy executing any.NPX – A tool for executing Node packages. NPX comes bundled with NPM version 5.2+ NPM by itself does not simply run any package. it doesn’t run any package in a matter of fact. If you want to run a package using NPM, you must specify that package in your package.json file. When executables are installed via NPM packages, NPM links to … Read more
There is the spyOn method, that was introduced with v19 some days ago, that does exactly what you are looking for
For the simple answer, you can use Link component from react-router, instead of button. There is ways to change the route in JS, but seems you don’t need that here. To do it programmatically in 1.0.x, you do like this, inside your clickHandler function: this.history.pushState(null, ‘login’); Taken from upgrade doc here You should have this.history … Read more
You should add a key to each child as well as each element inside children. This way React can handle the minimal DOM change. In your code, each <TableRowItem key={item.id} data={item} columns={columnNames}/> is trying to render some children inside them without a key. Check this example. Try removing the key={i} from the <b></b> element inside … Read more
This is due to this.delta not being bound to this. In order to bind set this.delta = this.delta.bind(this) in the constructor: Currently, you are calling bind. But bind returns a bound function. You need to set the function to its bound value.
Yes there is a difference! The immediate effect of using innerHTML versus dangerouslySetInnerHTML is identical — the DOM node will update with the injected HTML. However, behind the scenes when you use dangerouslySetInnerHTML it lets React know that the HTML inside of that component is not something it cares about. Because React uses a virtual … Read more