Simply use v-bind like :ref="'element' + result.id" or ref="`element${result.id}`".
Check fiddle here.
new Vue({
el: '#app',
data: {
data: [{id: 1}, {id: 2}, {id: 3}],
},
mounted() {
console.log(this.$refs);
}
})<script src="https://cdnjs.cloudflare.com/ajax/libs/vue/2.4.2/vue.min.js"></script>
<div id="app">
<div v-for="(result, index) in data" :key="index">
<input type="text" type="file" :ref="'element' + result.id" />
</div>
</div>Edited:
Thanks to Vamsi’s edit, I replaced index with result.id
Edited 8/28:
Thanks to grokpot, I added a sample powered by Template literals.