for example, I want the textfield input number only. my idea is when the user typing, it will call a javascript to check whether it is valid, if it is not valid, I delete the text which is just entered. But I think it is very complex to do so. Is there any simple way to do so?
Put a validation on submit.
JQuery Masking could be a good choice: http://digitalbush.com/projects/masked-input-plugin/
The script to do this is here. It's a pretty common requirement.
http://javascript.internet.com/forms/validate-numeric-only.html
I think, like o.k.w said, jQuery Masking would be a good choice because of 2 things:
jQuery is solid and fast
Masking is more user friendly than just deleting user input on the fly without any notification. Masking gives them a graphical reference of what type of input is expected and what the input might look like.
Related
I have a more or less complex SPA with ~40 text input fields. Those input elements are not bundled by a <form>, but they are separated into categories. If a user submits, i would like to trigger a validation function.
My first approach was writing two directives, one for string input and one for numeric values, which would add an attribute to every invalid element, then using a validate() function which would look up every input field in order to check whether or not it has said attribute.
I stumbled over multiple issues, including the fact that this was a jQuery like solution to the problem.
How could i accomplish this in a more convenient way?
One of the ways I have been handling form validation when things are not inside of a form is by using ng-pattern. With ng-pattern you can either do direct regex there, or link to an expression to run a set of validations for you.
It would look something like this.
<input type="text" ng-pattern="Put your Regex Here or an Expression">
The angular docs for ng-pattern are pretty sparse, so good luck.
This approach may not be what you are looking for since it evaluates only one input at a time, but I hope this helps.
what is the most effective way to make a jquery field validation? For example if field name is empty, it will add empty checkmark next to field? I understand, that PHP validation is needed, and I have it, so no worries about that.
You can try JQuery inline validation.
From here you can try out many examples
http://www.position-absolute.com/articles/jquery-form-validator-because-form-validation-is-a-mess/
Can any one suggest to build a password field that behaves the way passwords are entered using iphone?
When I enter some character, it should be visible to the user for a second and then it should turn to *. But I need to get the value from the field when I submit the form.
Its an ExtJs text field. Is there any plugins available for this? Any help on this will be helpful.
Probably, this can help you:
http://blog.decaf.de/2009/07/iphone-like-password-fields-using-jquery/
Check out this Fiddle
Change textfield to stars like iPhone
Note: this solution is NOT complete and NOT optimal, for example you will have to handle Delete and Backspace buttons manually. You might find some plugin to do it in other way, but this is the simplest way to do it JavaScript I guess.
I have a script in a web application of mine which forces users to type only numbers into certain text fields. However, when the appropriate text field is selected, the script blocks ANY keyboard input other than number keys and tab. I don't want to limit the user from being able to use their browser's or my app's keyboard shortcuts just because they are typing in a numerical field. (Also, I'd rather not just validate the field instead of preventing number input, my app updates the page based on the numerical input live, so it wouldn't be as nice.)
Can someone please help write/find a little script for me? A simple variation of these numbers-only scripts that can be overrided when a modifier key is pressed is enough (and I guess the overrided character would have to be deleted, too).
I'm not going to write a script for you, but I'll give you some pseudo-pseudo-code:
input = input.replace(/\D/, '');
Try YAV, Javascript validator library.
I think you need mask feature.
Look at field Custom: from this example
http://yav.sourceforge.net/en/example_7.html
I'm trying to reduce the form spam on our website. (It's actually pretty recent).
I seem to remember reading somewhere that the spammers aren't executing the Javascript on the site.
Is that true?
And if so, then could you simply check for javascript being disabled and then figure it's likely that it's spam?
There are still a large number of people that run with Javascript turned off.
Alternatively, I have had decent success with stopping form spam using CSS. Basically, include an input field and label that is hidden using CSS (display: none;) and once submitted, check if anything has been entered in the field.
I generally label the field as a spam filter with an instruction to not put anything in the field, but all newer browsers will properly hide the block.
More: Fighting Spam with CSS
reCAPTCHA is also surprisingly easy to implement.
check http://kahi.cz/wordpress/ravens-antispam-plugin/ for a nice answer
if puts in
<noscript><p><label for="websiteurl99f">Please type "e73053": </label><input type="text" name="websiteurl99f" id="websiteurl99f" /></p></noscript>
<script type="text/javascript">/* <![CDATA[ */ document.write('<div><input type="hidden" name="websiteurl99f" value="e' + '73053" \/><\/div>'); /* ]]> */</script>
so javascript users see nothing, non js users just type in a word
if a spammer targets you specifically it won't take them long to code round it but for drive by spammers it should be good
In the same vein, adding a dummy field and then using CSS to hide it is a good way to trick the bots. If the field is submitted, you know a non-human probably completed the form.
Especially effective if you label/name the field something along the lines of URL or website.
You could check - have JavaScript that populates a hidden form field with a specific value after the page loads. Then, when the page posts back to the server, check that hidden form field the expected value. If it is not there, that means the JavaScript didn't execute.
As to whether you should assume it is spam is another story altogether, and one that has no certain answer, really. You could simply have a <noscript> tag and have it indicate to the user that their submission will not take unless they enable JavaScript.
Once you have JavaScript running, however, the spammers will just use another workaround for that. :)
I can't remember where I've seen this method but spam bots like to fill out forms. Have you considered putting a form field that is hidden with javascript (and says don't fill this field if the user doesn't have JavaScript). This way if something fills in this field you can ignore it as spam.
Did you have any luck with this? I think some text based browsers have implemented basic JavaScript support, so maybe spam bots have as well?
Otherwise I'm considering using a captcha for users without JavaScript and some automatic JavaScript check for other users.