function 检查验证是否为真，然后执行此操作

Question

I'm trying to make this work.

JS validation:

function validation() {
  var fname = document.getElementById('fname').value;
  if (fname == '') {
    document.getElementById('fn').innerHTML = 'Please enter first name.';
  }
  var lname = document.getElementById('lname').value;
  if (lname == '') {
    document.getElementById('ln').innerHTML = 'Please enter last name.';
  }
  var birth = document.getElementById('birthdate').value;
  if (birth == '') {
    document.getElementById('bday').innerHTML = 'Please enter birthdate.';
  }
  var gender = document.getElementById('gender').value;
  if (gender == 'select') {
    document.getElementById('gndr').innerHTML = 'Please choose your gender.';
  }
  var username = document.getElementById('username').value;
  if (username == '') {
    document.getElementById('usr').innerHTML = 'Please enter username.';
  }
  var email = document.getElementById('email').value;
  if (email == '') {
  }
  var econf = document.getElementById('econf').value;
  if (econf == '') {
    document.getElementById('rt-eml').innerHTML = 'Please confirm your email.';
  }
  if (econf != email) {
    document.getElementById('rt-eml').innerHTML = 'Email did not match.';
  }
  var password = document.getElementById('password').value;
  if (password == '') {
    document.getElementById('pass').innerHTML = 'Please enter password.';
  }
  var pconf = document.getElementById('pconf').value;
  if (pconf == '') {
    document.getElementById('rt-pass').innerHTML =
      'Please confirm your password.';
  }
  if (pconf != password) {
    document.getElementById('rt-pass').innerHTML =
      'Password did not match. Try again. ';
  } 
}

I want my check function to check if validation is true then change the innerHTML of success to You have successfully created an account.

JS check function:

function check() {
  if (validation === true) {
    document.getElementById('success').innerHTML =
      'Your account has been successfully created.';
  }
}

I know it's kinda messed up and I admit I'm still new to this.

Answer 1

A common way to do it is to initialize a boolean to true , if any field is empty or not valid then you assign false to this boolean. You return its value at the end of the validation function.

function check() {
  //no need to check === true here
  if (validation()) {
    document.getElementById('success').innerHTML =
      'Your account has been successfully created.';
  }
}

function validation() {
  let isValid = true;
  var fname = document.getElementById('fname').value;
  if (fname == '') {
    document.getElementById('fn').innerHTML = 'Please enter first name.';
    isValid = false;
  }
  var lname = document.getElementById('lname').value;
  if (lname == '') {
    document.getElementById('ln').innerHTML = 'Please enter last name.';
    isValid = false;
  }
  var birth = document.getElementById('birthdate').value;
  if (birth == '') {
    document.getElementById('bday').innerHTML = 'Please enter birthdate.';
    isValid = false;
  }
  var gender = document.getElementById('gender').value;
  if (gender == 'select') {
    document.getElementById('gndr').innerHTML = 'Please choose your gender.';
    isValid = false;
  }
  var username = document.getElementById('username').value;
  if (username == '') {
    document.getElementById('usr').innerHTML = 'Please enter username.';
    isValid = false;
  }
  var email = document.getElementById('email').value;
  if (email == '') {
    isValid = false;
  }
  var econf = document.getElementById('econf').value;
  if (econf == '') {
    document.getElementById('rt-eml').innerHTML = 'Please confirm your email.';
    isValid = false;
  }
  if (econf != email) {
    document.getElementById('rt-eml').innerHTML = 'Email did not match.';
    isValid = false;
  }
  var password = document.getElementById('password').value;
  if (password == '') {
    document.getElementById('pass').innerHTML = 'Please enter password.';
    isValid = false;
  }
  var pconf = document.getElementById('pconf').value;
  if (pconf == '') {
    document.getElementById('rt-pass').innerHTML =
      'Please confirm your password.';
    isValid = false;
  }
  if (pconf != password) {
    document.getElementById('rt-pass').innerHTML =
      'Password did not match. Try again. ';
    isValid = false;
  }
  return isValid;
}