文件点击下载

// 点击文件下载，fileUrl为http的url
function downloadFile(fileUrl) {
    fetch(fileUrl).then(res => res.blob()).then(blob => {
        const a = document.createElement('a')
        document.body.appendChild(a)
        a.style.display = 'none'
        const url = window.URL.createObjectURL(blob)
        a.href = url
        a.download = fileUrl
        a.click()
        document.body.removeChild(a)
        window.URL.revokeObjectURL(url)
    })
}