React Js Map Example

While creating components using the map, react expects a key prop passed to each component being built. Mapping data from list.js file to custom info component using the map function. Delete () removes a map element specified by the key.

Get () gets the value for a key in a map. In the example below, we have 2 props patterns, i.e counter and list, and are combined in an application using render through reactdom.render in index.js file. It will still render if the key is not passed, but you will see a warning from react about it in the console.

Var numbers = [1, 2, 3, 4, 5];

In the example below, we have 2 props patterns, i.e counter and list, and are combined in an application using render through reactdom.render in index.js file. Map () does not execute the function for empty elements. Mapping data from list.js file to custom info component using the map function. The answer is, you use array.map () in your component and return jsx elements inside the array.map () callback function to render the ui.