v-model= selected events
<select name="LeaveType" @change="onChange($event)" class="form-control" v-model="key">
<option value="1">Annual Leave/ Off-Day</option>
<option value="2">On Demand Leave</option>
</select>
<script>
var vm = new Vue({
data: {
key: ""
},
methods: {
onChange(event) {
console.log(event.target.value)
}
}
}
</script>