downloadFileTest.html

<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>__小简__下载测试</title>
    <style>
        div {
            width: 100%;
            text-align: center;
            margin-top: 50px;
        }
    </style>
    <script>
        window.onload=function(){
            var oBtnDownload=document.getElementById('download');
            oBtnDownload.onclick=function(){
                window.open('http://localhost:3000/download', '_blank')
            }
        }
    </script>
</head>

<body>
    <div>
        <button id="download">点击下载</button>
    </div>
</body>

</html>