import React, { Component } from 'react'; import { render } from 'react-dom'; const TextInput = React.forwardRef((props, ref) => ( <input type="text" placeholder="Hello World" ref={ref} /> )); const inputRef = React.createRef(); class CustomTextInput extends React.Component { handleSubmit = e => { e.preventDefault(); console.log(inputRef.current.value); }; render() { return ( <div> <form onSubmit={e => this.handleSubmit(e)}> <TextInput ref={inputRef} /> <button>Submit</button> </form> </div> ); } } export default App;
Question
import React, { Component } from 'react'; import { render } from 'react-dom'; const TextInput = React.forwardRef((props, ref) => ( <input type="text" placeholder="Hello World" ref={ref} /> )); const inputRef = React.createRef(); class CustomTextInput extends React.Component { handleSubmit = e => { e.preventDefault(); console.log(inputRef.current.value); }; render() { return ( <div> <form onSubmit={e => this.handleSubmit(e)}> <TextInput ref={inputRef} /> <button>Submit</button> </form> </div> ); } } export default App;
Solution
The code you've posted is written in JavaScript, specifically using the React library. It defines a text input component and a form that uses this input. When the form is submitted, it logs the current value of the text input.
Here's a step-by-step breakdown:
-
TextInputis a functional component that uses theforwardReffunction from React to pass arefto the input element. This allows us to directly interact with the DOM element. -
inputRefis a reference object created usingReact.createRef(). This will be used to access the value of the input field. -
CustomTextInputis a class component. It has a methodhandleSubmitthat prevents the default form submission behavior and logs the current value of the input field referenced byinputRef. -
In the
rendermethod ofCustomTextInput, a form is returned. The form contains theTextInputcomponent and a submit button. TheonSubmitprop of the form is set to thehandleSubmitmethod. -
The
refprop ofTextInputis set toinputRef, which means theinputRefnow points to the actual input DOM element. -
The
CustomTextInputcomponent is exported as a default export.
Please note that the last line export default App; seems to be a mistake as there is no App component defined in the provided code. It should be export default CustomTextInput; instead.
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