Menggunakan FILEREADER Javascript

 

1. HTML

<input type="file" id="foto" onchange="preview(event)" />

2. Javascript

<script type="text/javascript">

function preview(event){

  const reader = new FileReader();

  reader.addEventListener("load",()=>{

      console.log(reader.result);

      // function upload(reader.result) => jika ingin menggunakan data base64 di fungsional lainnya.

  })

  reader.readAsDataURL(event.target.files[0]);

}

</script>