前端js读取本地md或txt文件内容

<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>前端js读取本地md或txt文件内容</title>
  </head>
  <body>
    <script>
      function readTextFile(fileName) {
        var rawFile = new XMLHttpRequest()
        var filePath = location.origin + '/' + fileName
        rawFile.open('GET', fileName, false)
        rawFile.onreadystatechange = function () {
          if (rawFile.readyState === 4) {
            if (rawFile.status === 200 || rawFile.status == 0) {
              var allText = rawFile.responseText
              document.getElementById('showmd').innerHTML = allText
              console.log(666.20001, allText, location)
            }
          }
        }
        rawFile.send(null)
      }
    </script>
    <div id="showmd"></div>
    <button onclick="readTextFile('text.md')">测试按钮</button>
    <button onclick="readTextFile('public/text.md')">测试按钮2</button>
  </body>
</html>