Preventing leading white space in input field pattern - html

Problem
I'm trying to prevent leading whitespace from being used in an input whether through spaces or tabs by using a pattern, but I'm having issues with this regular expression ^(?!\s)([a-zA-Z0-9 _.'"()!?&#]){1,}$, which I think is because I might not be escaping properly because of the quotation marks?
Ultimately, I want to make sure the input takes at least one character, but none of those characters be leading white space at the beginning of the query.
Invalid inputs
_This is a query
__This is a query
Valid inputs
This is a good input
abc
123
a
index.html
<form action="{% url 'master_search' %}" method="GET">
<i class="fa fa-search search-icon-drilldown" aria-hidden="true"></i>
<input type="text" class="nav__search--agency form-control inline" name="q" value="" placeholder="Search by employee name" pattern="^(?!\s)([a-zA-Z0-9 _.'"()!?&#]){1,}$" required>
</form>

Hm. If you want to allow everything that starts with a letter or number,
pattern="^[a-zA-Z1-9].*"
should do the job

You could also negate a range by doing
^[^\s]+.*$
which will match a line with a starting character that is not white space.

This is A pattern , which is uses to input type in html, but for name validation I have been analysise the pattern
pattern="^(?!\s)[a-zA-Z ]{1,}$" and I used the title (title="Request Format:Not valid numeric val & special character. Only Character") for Requested pattern form in my input type html form where type="name"

Related

Pattern attribute not working as expected?

So I'm trying to make a form for my assignment, and I am using the pattern attribute in html so only certain characters are required to be typed on the text box. But for some reason, the form is saying using that I'm using an incorrect format even though I made my pattern attribute that way.
Here's an example of the code and a picture of the problem.
<form>
<label for="mnumber">Mobile Number:</label>
<input type="text" required id="mnumber" pattern="[0-9]"><br><br>
<input type="submit" value="submit">
</form>
You did write:
pattern="[0-9]"
You are asking for only one number. You just forget to add '+' to accept more than one number. I guess what you are searching for is this:
pattern="[0-9]+"
pattern="[0-9]"
allows for only a single number character to validate (and be submitted). If you want to allow more than one character, here's your options:
One or more numbers:
pattern="[0-9]+"
Zero or more numbers:
pattern="[0-9]*"
One to three numbers:
pattern="[0-9]{1,3}"
you just need to change type="text" to type="number"

Pattern Attribute: Require at least 1 non-whitespace character and allow white space before and after character

I'm trying to use the pattern attribute so that the form is able to submit as long as there's 1 non white space character in the form field:
<input type="text" class="form-control" id="agentName" name="agentName" placeholder="Agent Name" pattern=".*\S.*" title="This field is required">
However with this, the form doesn't submit if there's white space at the beginning or at the end. And it is adding in a period if I hit the spacebar after the character for whatever reason.
Thanks for your help
This should take do the trick:
.*[^\S].*

Regex to detect when certain characters or substrings

I'm currently using a regex to detect space, single-quote & double-quote in an input.
I would like to add the detection of several strings: ex. 'xxx' & 'yyy'. It should only detect for those complete strings, so 'x' or 'y' by itself wouldn't be detected.
Currently have this in html input code:
<input type="text" pattern="^(?=.*[\x27\x20\x22]).+$" ...
If you just want to ensure exactly one space, single-quote or double-quote appears in the input, you can simplify your pattern to:
<input type="text" pattern="[\x27\x20\x22]" ...
To detect other things, you can add "alternations", separated by |:
<input type="text" pattern="[\x27\x20\x22]|xxx|yyy" ...
As per jhnc: To detect any instance, no matter where in the string:
<input type="text" pattern=".*([\x27\x20\x22]|xxx|yyy).*" ...

HTML pattern validation on input elements

Abit annoying to work with since I cannot seem to get this right.
I need to get a pattern that accepts exactly 12 characters containing upper case letters and numbers. Nothing more nor less than 12 characters.
<input type="text" placeholder="Licence Number.." pattern="[A-Z0-9]+" maxlength="12" minlength="12" title="Enter Licence number">
I am going about this in a wrong way because everytime I am entering 12 characters it is activating the validation message.
You can remove the minlength attribute and use the pattern [A-Z0-9]{12} instead:
input:invalid {
color:red;
}
<input type="text" placeholder="Licence Number..." pattern="[A-Z0-9]{12}" maxlength="12" title="Enter Licence number">
The minlength attribute is not needed using the above pattern. The maxlength attribute isn't also needed with the above pattern but it stops the input after 12 chars.
At the moment your pattern allows all license numbers with at least one upper case letter or number.
I believe what you are missing in your regular expression is an exact count. Your regex will match if any input character matches your specification at least once. This means that no matter how long your input is, or how many "illegal" characters there are, if just one uppercase letter or digit is input, the regex will match.
The following will check for exactly 12 of any uppercase letter or digit.
[A-Z0-9]{12}

Why is my hidden HTML form field showing up?

I'm trying to put some data in a hidden form field for a POST. But the field is showing up on my Web page. There are no styles or style sheet. Here's how the fields are defined. Any ideas?
<form action="GetUserPics.php" method="post">
<input type=”hidden” name=”picIndex” value="WHAT?">
<input type="submit" value="previous">
</form>
You are using non-standard quotation marks for your attributes on that field. HTML is interpreting those quotes as part of the attribute's value, as in:
<input type="”hidden”" name="”picIndex”" value="WHAT?">
Since ”hidden” is not a valid input type, it's reverting to text.
Because you're not using ASCII quotes, you're using some sort of weird slanty quotes that the HTML is trying to use as the type (and thus it will fall back to text). Interestingly, you're not using them to print the value, which incidentally hides your mistake.
<input type=”hidden” name=”picIndex” value="WHAT?">
Those are not regular double quotes. Try
<input type="hidden" name="picIndex" value="WHAT?">
Can you replace your hidden type input with this:
<input type="hidden" name="picIndex" value="WHAT?"/>