JAVASCRIPT

javascript Validating the Phone Number

// program to validate the phone number
function validatePhone(num) {
    // regex pattern for phone number
    const re = /^(?([0-9]{3}))?[-. ]?([0-9]{3})[-. ]?([0-9]{4})$/g;
    // check if the phone number is valid
    let result = num.match(re);
    if (result) {
        console.log('The number is valid.');
    }
    else {
        let num = prompt('Enter number in XXX-XXX-XXXX format:');
        validatePhone(num);
    }
}

// take input
let number = prompt('Enter a number XXX-XXX-XXXX');

validatePhone(number);

validate phone number javascript

// Commonly used regular expression

// Check 2-9 characters, false if not matched, true if matched
const validateName = (name) => {
   const reg = /^[u4e00-u9fa5]{2,9}$/;
   return reg.test(name);
};
// Verify phone number
const validatePhoneNum = (mobile) => {
   const reg = /^1[3,4,5,6,7,8,9]d{9}$/;
   return reg.test(mobile);
};
// Check passwords consisting of 6 to 18 uppercase and lowercase alphanumeric underscores
const validatePassword = (password) => {
   const reg = /^[a-zA-Z0-9_]{6,18}$/;
   return reg.test(password);
};

validate mobile number in javascript

var val = number.value
if (/^d{10}$/.test(val)) {
    // value is ok, use it
} else {
    alert("Invalid number; must be ten digits")
    number.focus()
    return false
}