使用isNumeric检查输入中的数字

Question

I am trying to check if there is at least 1 digit in an input field. If there is I want to change the default image.

I am getting an error with the .isNumeric function. I know in the docs it shows $.isNumeric , but I am not sure how to add that within hasNumber.isNumeric().length >= 1; .

I am open to a different function if it will allow this to work.

 $('#register').keyup(function() { var hasNumber = $("#password").val(); var hasNumberValid = hasNumber.isNumeric().length >= 1; $('#upperCase').attr('src', hasNumberValid ? 'https://encrypted-tbn1.gstatic.com/images?q=tbn:ANd9GcQlyqJ14HYP1WclpK9RkJWo8jIDBkhTW0GS31AxRkozAEA72ULhY89LIzk' : 'icons/collection/delete.png'); }); 

 #password-check { margin: 30px auto; } .password-check-field { color: black; } .password-check-field img { margin-right: 15px; height: 15px; width: 15px; } 

 <script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script> <form action="" method="POST" id="register"> <div class="field"> <label for="firstname">First Name</label> <input type="text" name="firstname" required> </div> <div class="field"> <label for="password">Choose a password</label> <input type="password" name="password" id="password" required> </div> <div class="password-check-field"> <img id="upperCase" src="icons/collection/delete.png" alt="Success">Your password has at a number in it </div> </form> 

Answer 1

$.isNumeric() accepts an argument of any value, so you can pass in your $("#password").val() to it via:

$.isNumeric(hasNumber) or $.isNumeric( $("#password").val() )

The $.isNumeric() method checks whether its argument represents a numeric value. If so, it returns true . Otherwise it returns false . The argument can be of any type.

No need to use length on that one.

Answer 2

Try like this.

 $('#register').keyup(function() { var hasNumber = $("#password").val(); var hasNumberValid = false; var inputArray = hasNumber.split(''); inputArray.forEach(function(element) { if($.isNumeric(element)) { hasNumberValid = true } }); $('#upperCase').attr('src', hasNumberValid ? 'https://encrypted-tbn1.gstatic.com/images?q=tbn:ANd9GcQlyqJ14HYP1WclpK9RkJWo8jIDBkhTW0GS31AxRkozAEA72ULhY89LIzk' : 'icons/collection/delete.png'); }); 

 #password-check { margin: 30px auto; } .password-check-field { color: black; } .password-check-field img { margin-right: 15px; height: 15px; width: 15px; } 

 <script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script> <form action="" method="POST" id="register"> <div class="field"> <label for="firstname">First Name</label> <input type="text" name="firstname" required> </div> <div class="field"> <label for="password">Choose a password</label> <input type="password" name="password" id="password" required> </div> <div class="password-check-field"> <img id="upperCase" src="icons/collection/delete.png" alt="Success">Your password has at a number in it </div> </form> 

Answer 3

isNumeric() returns a boolean. Check to see if it's true. Try using $.isNumeric()

var hasNumberValid = $.isNumeric(hasNumber)

Answer 4

您可以使用简单的正则表达式来检查字符串中是否有数字

var hasNumberValid = hasNumber.match(/\d+/g) != null;

Answer 5

I would put the keyup on your password field instead of the form and use a regular expression instead of isNumericn since the documentation states that "Description: Determines whether its argument represents a JavaScript number." I'm not sure whether it will be true in the case where you have both numbers and letters.

fiddle example

var AtLestOneLetterAndOneNumberRegex = new RegExp(".*[0-9].*");
$('#password').keyup(function() {
  var passwordValue = $("#password").val();
  if (AtLestOneLetterAndOneNumberRegex.test(passwordValue)){

    $("#validPasswordMessage").css("visibility","visible");
  }

});