如何在特定的按钮上使用Javascript和AJAX下载csv文件？

<button id="downloadBtn">下载CSV文件</button>

var downloadBtn = document.getElementById("downloadBtn");
downloadBtn.addEventListener("click", downloadCSV);

function downloadCSV() {
  var xhr = new XMLHttpRequest();
  xhr.open("GET", "path/to/csv/file", true);
  xhr.responseType = "blob";
  
  xhr.onload = function() {
    if (xhr.status === 200) {
      var blob = new Blob([xhr.response], { type: "text/csv" });
      var downloadLink = document.createElement("a");
      downloadLink.href = URL.createObjectURL(blob);
      downloadLink.download = "filename.csv";
      downloadLink.click();
    }
  };
  
  xhr.send();
}