Form Validation using RegEx in JavaScript.

 

Form Validation Using RegEx

 index.html file

<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8" />
  <meta name="viewport" content="width=device-width, initial-scale=1.0" />
  <meta http-equiv="X-UA-Compatible" content="ie=edge" />
  <title>Tinyone</title>
  <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css"
    integrity="sha384-BVYiiSIFeK1dGmJRAkycuHAHRg32OmUcww7on3RYdg4Va+PmSTsz/K68vbdEjh4u" crossorigin="anonymous" />

  <link href="css/style.css" rel="stylesheet" />

</head>

<body>
    <div class="container">
            <h2>Create Account Form</h2>
            <form action="" name="Registration">
              <div class="form-group">
                <label for="email">Email:</label>
                <input type="email" class="form-control" id="email" placeholder="Enter email" name="email">
                <label for="checkemail">Please Enter Proper Email ID</label>

              </div>
              <div class="form-group">
                <label for="pwd">Password:</label>
                <input type="password" class="form-control" id="pwd" placeholder="Enter password" name="pwd">
                <label for="checkpwd">PassWord Length Should be atleast 8 characters longer</label>
              </div>
              <div class="form-group">
                    <label for="Mobile">Phone Number:</label>
                    <input type="Mobile" class="form-control" id="mobile" placeholder="Enter Mobile Number " name="mob">
                    <label for="checkmob">Enter Proper Mobile Number</label>
                  </div>
              <button type="button" class="btn btn-default save">Submit</button>
            </form>
            <div id="result">

            </div>
    </div>
  

  <script src="https://code.jquery.com/jquery-3.4.1.js" integrity="sha256-WpOohJOqMqqyKL9FccASB9O0KwACQJpFTUBLTYOVvVU="
    crossorigin="anonymous"></script>
  <!-- Latest compiled and minified JavaScript -->
  <script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js"
    integrity="sha384-Tc5IQib027qvyjSMfHjOMaLkfuWVxZxUPnCJA7l2mCWNIpG9mGCD8wGNIcPD7Txa"
    crossorigin="anonymous"></script>
    <script src="js/app.js"></script>
</body>

</html>

app.js file

    var mybtn = document.querySelector(".save");
    mybtn.addEventListener("click",validate)
    
        function validate(){
        var email = document.getElementById("email").value;
        var isValidate = 0;
        var pass = document.getElementById("pwd").value;
        
        var mob = document.getElementById("mobile").value; 
    
        var pattermail = /^[\w-\.]+@([\w-]+\.)+[\w-]{2,4}$/;
        if(!email.match(pattermail)){
            document.querySelector("label[for='checkemail']").style= "display:block";
            isValidate += 1;
        }
        if(pass.length < 8){
            document.querySelector("label[for='checkpwd']").style= "display:block";
            isValidate += 1;
        }
        var patternmob = /^[0-9]{10}$/;
        if(!mob.match(patternmob)){
            document.querySelector("label[for='checkmob']").style= "display:block";
            isValidate += 1;
        }
        if(isValidate==0){
            document.getElementById("#result").innerHTML = "<h3>Account Successfully Created and Confirmation Mail Sent at"+email+"</h3>";
        }else{
            document.getElementById("#result").innerHTML = "<h3>Please Check All Fields</h3>";
        }
    }

style.css file

label[for="checkemail"] {
    color: red;
   display: none;
 }
 label[for="checkpwd"] {
    color: red;
    display: none;
  }
  label[for="checkmob"] {
    color: red;
    display: none;
  }
  h2 ,h3{
    text-align: center;
  }