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              <input type="file" id="file" class="btn">
<div id="result" class="result">ここに結果が表示されます</div>
              body {
  padding: 1%;

.btn {
  margin-bottom: 30px;
              window.onload = () => {
  const file = document.getElementById('file');
  const result = document.getElementById('result');
  //  FileReaderオブジェクトを生成
  const reader = new FileReader();
  // ファイルが選択されたらFileReaderオブジェクトにファイルをテキストとして保存
  file.addEventListener('change', function(e){
  // ファイルの読み込みが終わったら内容を表示
  reader.onload = function(e){
    result.innerText = e.target.result;
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