JS gets a simple instance of select value and text value

The code copy is as follows:

<select id = "cityList" >

<select id = "selectId" >

<option value = "0">0th</option>

</select>

<script>

var selectObj = document.getElementById('selectId');

// Add option through object

selectId.add(new Option("first","1"))

selectId.add(new Option("second","2"))

// Add option by id

selectId.add(new Option("third","3"))

selectId.add(new Option("Fourth","4"))

// Add methods through id (you can also add methods through objects)

selectId.onchange = function(){

// Get value and text through object

alert(selectObj.value);

alert(selectObj.options[selectObj.selectedIndex].text);

// Get value and text through id

alert(selectId.value);

alert(selectId.options[selectId.selectedIndex].text);

// You can also get value and text through this

alert(this.value);

alert(this.options[this.selectedIndex].text);

};

</script>