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}
Related
I need to create a registration form in HTML which has a password input with the following constraints:
Is a mandatory field, should be validated. Minimum of 7 characters. Should have at least one special character and one number. Do not use java script, use HTML 5 features.
I have written the following code to for the above input:
<input type="text" name="password" pattern="(?=.*\d)(?=.*[\W_]).{7,}" required>
I need to submit this code as part of an assignment and I get the error:
Correct HTML Component with the name 'password' must be used with appropriate constraints
which means I am not using the correct attributs.
What changes should I make to the pattern attribute?
This code works perfectly with validation message
<p>Password: <input type="password" name="pw" pattern="(?=.*\d)(?=.*[\W_]).{7,}" title="Minimum of 7 characters. Should have at least one special character and one number."></p>
try it here :
https://www.w3schools.com/tags/tryit.asp?filename=tryhtml5_input_pattern3
I think this will work.
Password:<input type="password" name="pw" pattern="^(?=.*?[a-z])(?=.*?[0-9])(?=.*?[#?!#$%^&*-]).{7,}$" title="Minimum of 7 characters. Should have at least one special character and one number and one UpperCase Letter.">
Pattern attribute will also use a Regular Expression to validate your form-data.So for more results you can also search for Regular Expression
I have tried to restrict users in HTML text box to insert only 4 digit numbers 0-9.
I have tried as follows but it restrict only to allow two digit numbers.
<input type="text" name="pincode" maxlength="4" id="pin" pattern="^0[1-9]|[1-9]\d$" required/>
Let me clarify: any of the ^[0-9]{4}$ or ^\d{4}$ are valid regexps to restrict values to 4 digits only. However, pattern HTML5 attribute value is already anchored by default:
The regular expression language used for this attribute is the same as that used in JavaScript, except that the pattern attribute is matched against the entire value, not just any subset (somewhat as if it implied a ^(?: at the start of the pattern and a )$ at the end).
So, use just pattern="\d{4}":
input:valid {
color: green;
}
input:invalid {
color: red;
}
<form name="form1">
<input type="text" name="pincode" maxlength="4" id="pin" pattern="\d{4}" required/>
<input type="Submit"/>
</form>
BTW, your ^0[1-9]|[1-9]\d$ pattern matches only 2 digit inputs because it matches either 0 followed by any digit from 1 to 9, or any digit from 1 to 9 followed by any digit.
Also, note that pattern="\d{4}" attribute does not prevent entering non-digit symbols into the field. See How to prevent invalid characters from being typed into input fields post how to solve that.
Please try adding the following:
<input type="text"
maxlength="7"
onkeypress='return event.charCode >= 48 && event.charCode <= 57'
required
/>
Change your pattern like below,
pattern = "^[0-9]{4}$"
Repeatation quantifier {4} should repeat the previous token exactly 4 times.
Change your regex like so:
pattern="\d{4}"
# allows numbers from 0000-9999
pattern="[1-9][0-9]{3}"
# from 1000-9999
A pattern like {1,4} would allow numbers with 1 up to 4 digits, a pattern like {x} fixes the number of digits to x times.
Edit: As #Tushar pointed out, the formerly regex [1-9]{4} was wrong as it did not allow any zeros.
pattern="\d{4}"
allows numbers from 0000-9999
pattern="[1-9][0-9]{3}"
allows numbers from 1000-9999
A pattern like {1,4} would allow numbers with 1 up to 4 digits. A pattern like {x} fixes the number of digits to x times.
I want a input box where it can only have alphabets and numbers with minimum number of letters of 4 and max of 20. To do this, I have the following code.
<input type="text" name="sample" pattern="[a-zA-Z0-9].{4,20}" />
This pattern attribute is preventing me from submitting the form. When I type something more than one letter, it tells me to match the required format.
What am I doing wrong? How can I have this form only take alphabets and numbers from 4-20 letters?
You are using the wildcard . in your pattern. It is what is being matched 4 to 20 times. Try
<input type="text" name="sample" pattern="[a-zA-Z0-9]{4,20}" />
Demo: http://jsfiddle.net/fwt2cj3o/
I'm writing a HTML form that submits through PHP and I'm wondering if there is a way to set a minimum number of characters in a number input?
For instance, for an Irish mobile phone number it needs to be exactly 10 digits. Is there a way to set this?
you can use HTML pattern Attribute with a regexp
<input type="text" name="phone number"
pattern="[A-Za-z]{10}" title="ten letter country code">
for regexp only numbres use this :
[0-9]{10}
Use regular expressions . It forces the user to enter 10 numbers between 0-9
Exact 10 letter /^[0-9]{10}/
<input type="number" pattern="[0-9]{10} "/>
I want to prevent the user from entering non-numeric characters in a textfield for telephone number in HTML5. I tried this, but it doesn't forbid non-numeric characters:
<input type="tel" name="usrtel"><br>
I tried using type=number as well, but that gives me a up and a down arrow to increase or decrease the value, which is not useful for telephone numbers. How can I accomplish this?
You can use pattern attribute with a regex \d*
<input type="tel" name="usrtel" pattern="\d*" />
Demo (After typing in the box, just click anywhere outside the box, if you type in anything except the integers, it will show a red box, else it will stay normal)
Demo 2 (With custom message and submit button)
As you commented, you can change your pattern value to ^[0-9]{3,45}$ where user will have to input minimal of 3 digits to maximum of 45 in length.
Demo
<input
type="tel"
name="usrtel"
pattern="^[0-9]{3,45}$"
title="You can only enter numbers, with a minimal of 3 characters
upto 45 characters are accepted."
required="required"
/>
In the above markup, am using a title which will throw a custom error to your user.