输入模式 - 手机号码 - 以特定数字开头

Question

I trying to configure the pattern to be able to submit a mobile number that should start with 09 followed by a '0-9' digits. Total max characters are 11.

Sample: 09 493432199 or 09 267778595

<form action="/action_page.php">
<label for="username">Username:</label>
<input type="text" id="username" name="username" pattern="[09]+[0-9]" maxlength="11"><br><br>
<input type="submit" value="Submit">
</form>

Answer 1

You can use this RegExp

It will match

• when the number starts with 09 AND

• when the number has exactly 11 digits

  pattern = /09[0-9]{9}/

Try it out here https://regex101.com/r/Nl2c2y/3

 <form action="/action_page.php"> <label for="username">Username:</label> <input type="text" id="username" name="username" pattern="09[0-9]{9}" maxlength="11"><br><br> <input type="submit" value="Submit"> </form>

Answer 2

Your html seems nice

  <form action="/action_page.php">
    <label for="username">Username:</label>
    <input type="text" id="username" name="username" pattern="[0-9]" maxlength="11"><br><br>
    <input type="submit" value="Submit">
    </form>

You need also have JS like follow:

var username_prefix = $('#username').subsubstr(0,2);
$('#validate').click(function(){
if (username_prefix == 09) {
alert('correct');
}
else {
    alert('incorrect');
}
});

Answer 3

Use an expression with fixed digits plus a specific amount of digits.

If you need the exact 11 characters, then use 09[0-9]{9}

In this example 09[0-9]{8,9} are valid 0912345678 and 09123456789

 <form action="/action_page.php"> <label for="username">Username:</label> <input type="text" id="username" name="username" pattern="09[0-9]{8,9}" maxlength="11"><br><br> <input type="submit" value="Submit"> </form>

As a side note, even if using input pattern is supported by the most common browsers, you should not rely only on the client side validation. Use a similar validation from the PHP backend to verify the information (in this case additional ^ (start of expression) and $ (end of expression) were added.

if (!preg_match("/^09[0-9]{9}$/",$_GET["username"])){
  // not valid
}

Answer 4

 <form action="/action_page.php">
    <label for="username">Username:</label>
    <input type="text" id="username" name="username" pattern="[0-9]" title="Zero is required" maxlength="11"><br><br>
    <input type="submit" value="Submit">
    </form>