Password validation for special characters in javascript

Question

I am writing a code for password validation that contains atleast: one small alphabet one capital alphabet one digit one special character min 8 and max 12 characters

but not able to validate the special character, rest all conditions mentioned above are working

HTML code:

<label for="psw"><b>Password <i class="fa fa-asterisk" style="font-size: 12px; color: red"></i>:</b></label>
<input id="pswd" name="pswd" type="password" placeholder="Enter Password" pattern="^(?=.*[a-z])(?=.*[A-Z])(?=.*[0-9])(?=.*[!@#$%^&*_=+-])$" title="Must contain at least one Special Character and one Number and one Uppercase and Lowercase letter, and at least 8 or more characters" required>  <br>

                <div id="message">
                    <h3>Password must contain the following:</h3>
                    <p id="letter" class="invalid">A <b>lowercase</b> letter</p>
                    <p id="capital" class="invalid">A <b>capital (uppercase)</b>letter</p>
                    <p id="number" class="invalid">A <b>number</b></p>
                    <p id="length" class="invalid">Minimum <b>8 characters</b></p>
                    <p id="spcl" class="invalid">A <b>Special character</b></p>
                    <p id="maxlength" class="invalid">Minimum <b>8 character</b> and Maximum <b>12 character</b></p>

                </div>

Javascript

 <script type="text/javascript">
         var myInput = document.getElementById("pswd");

         var letter = document.getElementById("letter");
         var capital = document.getElementById("capital");
         var number = document.getElementById("number");
         var maxlength = document.getElementById("maxlength");
         var spcl = document.getElementById("spcl");
// When the user clicks on the password field, show the message box
         myInput.onfocus = function () {
         document.getElementById("message").style.display = "block";
         }

         // When the user clicks outside of the password field, hide the message box
         myInput.onblur = function () {
         document.getElementById("message").style.display = "none";
                            }

         // When the user starts to type something inside the password field
          myInput.onkeyup = function () {
                            // Validate lowercase letters
                            var lowerCaseLetters = /[a-z]/g;
                            if (myInput.value.match(lowerCaseLetters)) {
                                letter.classList.remove("invalid");
                                letter.classList.add("valid");
                            } else {
                                letter.classList.remove("valid");
                                letter.classList.add("invalid");
                            }

                            // Validate capital letters
                            var upperCaseLetters = /[A-Z]/g;
                            if (myInput.value.match(upperCaseLetters)) {
                                capital.classList.remove("invalid");
                                capital.classList.add("valid");
                            } else {
                                capital.classList.remove("valid");
                                capital.classList.add("invalid");
                            }

                            // Validate numbers
                            var numbers = /[0-9]/g;
                            console.log(numbers);
                            if (myInput.value.match(numbers)) {
                                number.classList.remove("invalid");
                                number.classList.add("valid");
                            } else {
                                number.classList.remove("valid");
                                number.classList.add("invalid");
                            }
                            
                            var spcl = /[!@#$%^&*_=+-]/g;
                            console.log(spcl);
                            if (myInput.value.match(spcl)) {
                                spcl.classList.remove("invalid");
                                spcl.classList.add("valid");
                            } else {
                                console.log(myInput.value);
                                spcl.classList.remove("valid");
                                spcl.classList.add("invalid");
                            }


                            //Validate max length
                            if (myInput.value.length >= 8 && myInput.value.length <= 12) {
                                console.log('in min max condition');
                                console.log(myInput.value.length);
                                maxlength.classList.remove("invalid");
                                maxlength.classList.add("valid");
                            } else {
                                maxlength.classList.add("invalid");
                                maxlength.classList.remove("valid");
                            }
                        }
                    </script>

when I am checking for special character

                        var spcl = /[!@#$%^&*_=+-]/g;
                        console.log(spcl);
                        if (myInput.value.match(spcl)) {
                            spcl.classList.remove("invalid");
                            spcl.classList.add("valid");
                        } else {
                            console.log(myInput.value);
                            spcl.classList.remove("valid");
                            spcl.classList.add("invalid");
                        }

in console its showing error as : Uncaught TypeError: Cannot read properties of undefined (reading 'remove')

On printing the classList of variable 'spcl' I am getting the output as 'invalid' but still facing this Uncaught TypeError: Cannot read properties of undefined (reading 'remove')

You have two spcl variables, try renaming one of them – nedoder May 23 '22 at 11:24 — nedoder, May 23 '22 at 11:24

score 0 · Answer 1 · answered May 23 '22 at 11:25

0

check this question: Check for special characters in string

for special character use this:

var format = /[!@#$%^&*()_+\-=\[\]{};':"\\|,.<>\/?]+/;

if(format.test(string)){
  return true;
} else {
  return false;
}

answered May 23 '22 at 11:25

Amirhoseinh73

409
5
14

score 0 · Answer 2 · answered May 23 '22 at 11:27

0

With this you can check string contain the special character or not.

        //Regex for Valid Characters i.e. Alphabets, Numbers and Space.
        var regex = /^[A-Za-z0-9 ]+$/
 
        //Validate TextBox value against the Regex.
        var isValid = regex.test(document.getElementById("txtName").value);
        if (!isValid) {
            alert("Contains Special Characters.");
        } else {
            alert("Does not contain Special Characters.");
        }

answered May 23 '22 at 11:27

Raj Parmar

83
6

As it’s currently written, your answer is unclear. Please [edit] to add additional details that will help others understand how this addresses the question asked. You can find more information on how to write good answers [in the help center](/help/how-to-answer). – lemon May 23 '22 at 11:28

nedoder · Answer 3 · 2022-05-23T15:36:27.480

As I commented, you named two of your variables spcl. When you rename it, it works, there's nothing wrong with your regex. Also, I noticed you skipped min length validation, so I added it.

var myInput = document.getElementById("pswd");
var letter = document.getElementById("letter");
var capital = document.getElementById("capital");
var number = document.getElementById("number");
var maxlength = document.getElementById("maxlength");
var spcl = document.getElementById("spcl");
var length = document.getElementById("length");

// When the user clicks on the password field, show the message box
myInput.onfocus = function () {
   document.getElementById("message").style.display = "block";
  }

// When the user clicks outside of the password field, hide the message box
myInput.onblur = function () {
   document.getElementById("message").style.display = "none";
  }

// When the user starts to type something inside the password field
myInput.onkeyup = function () {
   // Validate lowercase letters
   var lowerCaseLetters = /[a-z]/g;
   if (myInput.value.match(lowerCaseLetters)) {
      letter.classList.remove("invalid");
      letter.classList.add("valid");
   } else {
      letter.classList.remove("valid");
      letter.classList.add("invalid");
   }

   // Validate capital letters
   var upperCaseLetters = /[A-Z]/g;
   if (myInput.value.match(upperCaseLetters)) {
      capital.classList.remove("invalid");
      capital.classList.add("valid");
   } else {
      capital.classList.remove("valid");
      capital.classList.add("invalid");
   }

   // Validate numbers
   var numbers = /[0-9]/g;
   console.log(numbers);
   if (myInput.value.match(numbers)) {
      number.classList.remove("invalid");
      number.classList.add("valid");
   } else {
      number.classList.remove("valid");
      number.classList.add("invalid");
   }
                            
   var special = /[!@#$%^&*_=+-]/g;
   console.log(special);
   if (myInput.value.match(special)) {
      spcl.classList.remove("invalid");
      spcl.classList.add("valid");
   } else {
      console.log(myInput.value);
      spcl.classList.remove("valid");
      spcl.classList.add("invalid");
   }


   //Validate max length
   if (myInput.value.length >= 8 && myInput.value.length <= 12) { 
      console.log('in min max condition');
      console.log(myInput.value.length);
      maxlength.classList.remove("invalid");
      maxlength.classList.add("valid");
  } else {
      maxlength.classList.add("invalid");
      maxlength.classList.remove("valid");
  }
  
  //Validate min length
   if (myInput.value.length >= 8) { 
      length.classList.remove("invalid");
      length.classList.add("valid");
  } else {
      length.classList.add("invalid");
      length.classList.remove("valid");
  }
}

.invalid {
color: red
}

.valid {
color: green
}

<label for="psw"><b>Password <i class="fa fa-asterisk" style="font-size: 12px; color: red"></i>:</b>
    </label>
    <input id="pswd" name="pswd" type="password" placeholder="Enter Password" pattern="^(?=.*[a-z])(?=.*[A-Z])(?=.*[0-9])(?=.*[!@#$%^&*_=+-])$" title="Must contain at least one Special Character and one Number and one Uppercase and Lowercase letter, and at least 8 or more characters" required><br>
    <div id="message">
       <h3>Password must contain the following:</h3>
       <p id="letter" class="invalid">A <b>lowercase</b> letter</p>
       <p id="capital" class="invalid">A <b>capital (uppercase)</b>letter</p>
       <p id="number" class="invalid">A <b>number</b></p>
       <p id="length" class="invalid">Minimum <b>8 characters</b></p>
       <p id="spcl" class="invalid">A <b>Special character</b></p>
       <p id="maxlength" class="invalid">Minimum <b>8 character</b> and Maximum <b>12 character</b>
       </p>
    </div>

Password validation for special characters in javascript

3 Answers3