js下载文件的方法

<a href="path/to/file.pdf" download="filename.pdf">Download PDF</a>

function downloadFile(content, filename, mimeType) {
    const blob = new Blob([content], { type: mimeType });
    const url = URL.createObjectURL(blob);
    const a = document.createElement('a');
    a.href = url;
    a.download = filename;
    document.body.appendChild(a);
    a.click();
    document.body.removeChild(a);
    URL.revokeObjectURL(url);
}

// 使用示例
downloadFile('Hello, world!', 'hello.txt', 'text/plain');

const data = new Blob(['Hello, world!'], { type: 'text/plain' });
const url = URL.createObjectURL(data);
const a = document.createElement('a');
a.href = url;
a.download = 'hello.txt';
document.body.appendChild(a);
a.click();
document.body.removeChild(a);
URL.revokeObjectURL(url);

fetch('path/to/file.pdf')
    .then(response => response.blob())
    .then(blob => {
        const url = URL.createObjectURL(blob);
        const a = document.createElement('a');
        a.href = url;
        a.download = 'file.pdf';
        document.body.appendChild(a);
        a.click();
        document.body.removeChild(a);
        URL.revokeObjectURL(url);
    })
    .catch(console.error);