how to set a placeholder for a <select> element code example

Example 1: html select placeholder

Placeholder attribute does not exist for the <select> tag.
But there are some ways to make a placeholder for the select box.
The easiest way of making a placeholder for the <select> element is using the disabled and selected attributes with the HTML5 hidden global attribute.
  
<select name="monthname" required>
  <option value="" selected disabled hidden>Select Month</option>
  <option value="Jan">January</option>
  <option value="Feb">February</option>
  <option value="Mar">March</option>
  <option value="Apr">April</option>
  <option value="May">May</option>
  <option value="Jun">June</option>
  <option value="Jul">July</option>
  <option value="Aug">August</option>
  <option value="Sep">September</option>
  <option value="Oct">October</option>
  <option value="Nov">November</option>
  <option value="Dec">December</option>
</select>

Example 2: html select placeholder

//angular
//<select> tag doesn't have any placeholder attribute.
//But you can make a placeholder by making
//your first option disabled and selected.
//Maybe you would want that option to be hidden,
//just add hidden
//in Angular you need to add value="undefined"
<select name="gender" required>
  <option value="undefined" selected disabled hidden>Select a Gender</option>
  <option value="Female">Female</option>
  <option value="Male">Male</option>
  <option value="Intersex">Intersex</option>
  <option value="Trans">Trans</option>
  <option value="Non-Conforming">Non-Conforming</option>
  <option value="Personal">Personal</option>
  <option value="Eunuch">Eunuch</option>
</select>