password validation check for letters and numbers

mat41 · August 27th, 2009, 12:27 AM

This function seems to work except for the checking for a string that contains letters and at least one number. please help?

function ValidatePW() {
var error = "";
var illegalChars = /[\W_]/; // allow only letters and numbers
var fld = document.updateForm.tUserPassword

if (fld.value == "") {
fld.style.background = 'Yellow';
alert("You didn't enter a password.\n");
} else if ((fld.value.length < 8) || (fld.value.length > 15)) {
alert("The password must be a minimum of eight characters.");
fld.style.background = 'Yellow';
} else if (illegalChars.test(fld.value)) {
alert("The password contains illegal characters, enter letters and numbers only.");
fld.style.background = 'Yellow';
} else if (!((fld.value.search(/(a-z)+/)) && (fld.value.search(/(0-9)+/)))) {
alert("The password must contain at least one number.");
fld.style.background = 'Yellow';
} else {
fld.style.background = 'White';
}
}

TYIA

om_prakash · August 27th, 2009, 01:11 AM

Hi, Please check the following function:

Code:

<script type="text/javascript">
  function checkForm(form)
  {
    if(form.username.value == "") {
      alert("Error: Username cannot be blank!");
      form.username.focus();
      return false;
    }
    re = /^\w+$/;
    if(!re.test(form.username.value)) {
      alert("Error: Username must contain only letters, numbers and underscores!");
      form.username.focus();
      return false;
    }
    if(form.pwd1.value != "" && form.pwd1.value == form.pwd2.value) {
      if(form.pwd1.value.length < 6) {
        alert("Error: Password must contain at least six characters!");
        form.pwd1.focus();
        return false;
      }
      if(form.pwd1.value == form.username.value) {
        alert("Error: Password must be different from Username!");
        form.pwd1.focus();
        return false;
      }
      re = /[0-9]/;
      if(!re.test(form.pwd1.value)) {
        alert("Error: password must contain at least one number (0-9)!");
        form.pwd1.focus();
        return false;
      }
      re = /[a-z]/;
      if(!re.test(form.pwd1.value)) {
        alert("Error: password must contain at least one lowercase letter (a-z)!");
        form.pwd1.focus();
        return false;
      }
      re = /[A-Z]/;
      if(!re.test(form.pwd1.value)) {
        alert("Error: password must contain at least one uppercase letter (A-Z)!");
        form.pwd1.focus();
        return false;
      }
    } else {
      alert("Error: Please check that you've entered and confirmed your password!");
      form.pwd1.focus();
      return false;
    }
    alert("You entered a valid password: " + form.pwd1.value);
    return true;
  }
</script>

Above script checks for following:
a) at least n characters
b) combination of upper- and lower-case characters
c) one or more digits
d) not related to other user data (name, address, username, ...)
e) not a dictionary word
http://www.the-art-of-web.com/javascript/validate/1/

mat41 · August 27th, 2009, 01:22 AM

Excellent that works a treat. Thankyou for your time :o)