put phone number pattern in input code example

Example 1: how to validate mobile number in html form

<div>
  <label for="phone">Enter your phone number:</label>
<input type="tel" id="phone" name="phone"  pattern="+94[7-9]{2}-[0-9]{3}-[0-9]{4}" value="+94">
 </div>

Example 2: tel pattern

<form>
  <div>
    <label for="country">Choose your country:</label>
    <select id="country" name="country">
      <option>UK</option>
      <option selected>US</option>
      <option>Germany</option>
    </select>
  </div>
  <div>
    <p>Enter your telephone number: </p>
    <span class="areaDiv">
      <input id="areaNo" name="areaNo" type="tel" required
             placeholder="Area code" pattern="[0-9]{3}"
             aria-label="Area code">
      <span class="validity"></span>
    </span>
    <span class="number1Div">
      <input id="number1" name="number1" type="tel" required
             placeholder="First part" pattern="[0-9]{3}"
             aria-label="First part of number">
      <span class="validity"></span>
    </span>
    <span class="number2Div">
      <input id="number2" name="number2" type="tel" required
             placeholder="Second part" pattern="[0-9]{4}"
             aria-label="Second part of number">
      <span class="validity"></span>
    </span>
  </div>
  <div>
    <button>Submit</button>
  </div>
</form>