$(function(){

    $('#demo').on('drop', function(e) {
        e.preventDefault();
        var $result_body = $('<table>');
        $('#demo').append($result_body);

        var files = e.originalEvent.dataTransfer.files[0];
        var reader = new FileReader();
        var ary = [];

        console.log(files.name);
        reader.onload = function(event) {

            var lineArr = event.target.result.split("\n");

            var itemArr = [];
            var lineAry = [];
            for (var i = 0; i < lineArr.length; i++) {
                itemArr[i] = lineArr[i].split(",");
            }

            var insert = '';
            for (var i = 0; i < itemArr.length; i++) {
                insert += '<tr>';
                for (var j = 0; j < itemArr[i].length; j++) {
                      insert += '<td>' + itemArr[i][j] + '</td>';
                      lineAry.push(itemArr[i][j]);
                }
                insert += '</tr>';
                ary.push(lineAry);
            }
            $result_body.html(insert);
        }
        console.log(ary);
        reader.readAsText(files, 'Shift_JIS');
    }).on("dragenter", function() {
        return false;
    }).on("dragover", function() {
        return false;
    });
});

#demo td{
  border:1px solid #000;
  padding:4px;
}

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view-source:https://hi0a.com/demo/-js/js-csv-drag-drop/