downloadFileFromBlobByToken

pdf 等所有文件通过blog强制下载函数 downloadFileFromBlobByToken

import { getToken } from '@/libs/util'
export const downloadFile = src => {
  console.log(src)
  let iframe = document.createElement('iframe')
  iframe.src = src
  iframe.style.display = 'none'
  iframe.style.height = 0
  document.body.appendChild(iframe)
  setTimeout(() => {
    iframe.remove()
  }, 3000)
}

/* 通过BLob文件来下载保存文件 */
const downloadFileFromBlob = (blob, fileName) => {
  // fileName 一定是要带后缀名的，而且要和blob匹配，否则下载文件打不开
  if (window.navigator && window.navigator.msSaveOrOpenBlob) { // IE系列兼容,兼容IE10+，Edge12-18
    window.navigator.msSaveOrOpenBlob(blob, fileName)
  } else {
    const downloadElement = document.createElement('a')
    const href = window.URL.createObjectURL(blob)
    downloadElement.href = href
    downloadElement.download = fileName
    document.body.appendChild(downloadElement)
    downloadElement.click()
    document.body.removeChild(downloadElement)
    window.URL.revokeObjectURL(href)
  }
}
const getFilenameFromUrl = (url) => {
  var anchor = url.indexOf('#')
  var query = url.indexOf('?')
  var end = Math.min(anchor > 0 ? anchor : url.length, query > 0 ? query : url.length)
  return url.substring(url.lastIndexOf('/', end) + 1, end)
}

const populateIframe = (url, headers, callback) => {
  var xhr = new XMLHttpRequest()
  xhr.open('GET', url)
  xhr.responseType = 'blob'
  headers.forEach((header) => {
    xhr.setRequestHeader(header[0], header[1])
  })
  xhr.onreadystatechange = () => {
    if (xhr.readyState === xhr.DONE) {
      if (xhr.status === 200) {
        // const disposition = xhr.getResponseHeader('content-disposition')
        // console.info('xhr.getAllResponseHeaders()', xhr.getAllResponseHeaders())
        // console.info('disposition', disposition)
        // const matched = /.*filename=(.*)/.exec(disposition) // 匹配
        // console.info('matched', matched)
        // const matchStr = matched?.[1]?.trim()
        // console.info('matchStr', matchStr)
        // console.info('decodeURI(matchStr)', decodeURI(matchStr))
        // console.info('decodeURIComponent(escape(matchStr))',
        //   decodeURIComponent(escape(matchStr)))
        // console.info('1+2+3',
        //   decodeURI(decodeURIComponent(escape(matchStr))))
        // downloadFileFromBlob(xhr.response, decodeURI(matchStr))
        const fileName = getFilenameFromUrl(url)
        console.info('fileName', fileName)
        downloadFileFromBlob(xhr.response, decodeURI(fileName))
        // downloadFileFromBlob(xhr.response, decodeURIComponent(escape(matchStr)))
        // callback && callback(URL.createObjectURL(xhr.response))
        // callback && callback(URL.createObjectURL(xhr))
        // callback && callback(URL.createObjectURL(xhr.response))
      }
    }
  }
  xhr.send()
}
export const downloadFileFromBlobByToken = (downloadFileUrl) => {
  console.info('downloadFileFromBlobByToken downloadFileUrl', downloadFileUrl)
  const headers = [
    ['token', getToken()]
  ]
  populateIframe(downloadFileUrl, headers)
}