How to validate mobile number length in ReactJS ?

Validating mobile number length is an important step to check whether the number entered by the user is genuine or not. Material UI for React has this component available for us and it is very easy to integrate. We can use the error Property for TextField Component in ReactJS using the following approach.

Creating React Application And Installing Module:

Step 1: Create a React application using the following command:

npx create-react-app foldername

Step 2: After creating your project folder i.e. foldername, move to it using the following command:

cd foldername

Step 3: After creating the ReactJS application, Install the material-ui modules using the following command:

npm install @material-ui/core

Project Structure: It will look like the following.

Project Structure

App.js: Now write down the following code in the App.js file. Here, App is our default component where we have written our code.

Javascript

import React, { useState } from "react";
import TextField from "@material-ui/core/TextField";
import InputAdornment from "@material-ui/core/InputAdornment";

const App = () => {
    const [mobile, setmobile] = useState("");
    const [isError, setIsError] = useState(false);

    return (
        <div
            style={{
                marginLeft: "40%",
            }}
        >
            <h2>Validate Mobile number length in ReactJS?</h2>
            <TextField
                type="tel"
                error={isError}
                value={mobile}
                label="Enter Phone Number"
                onChange={(e) => {
                    setmobile(e.target.value);
                    if (e.target.value.length > 10) {
                        setIsError(true);
                    }
                }}
                InputProps={{
                    startAdornment: <InputAdornment position="start">
                        +91
                    </InputAdornment>,
                }}
            />
            <h3>Your Mobile Number is: +91 {mobile} </h3>
        </div>
    );
};

export default App;

Step to Run Application: Run the application using the following command from the root directory of the project.

npm start

Output: Now open your browser and go to http://localhost:3000/, you will see the following output. In the above example, we can see when the user exceeds the 10 digits, the TextField color turns to red to indicate the error, this is how we can validate mobile number length in ReactJS.