wsemi
Version:
A support package for web developer.
56 lines (41 loc) • 1.1 kB
JavaScript
import genPm from './genPm.mjs'
/**
* 前端Blob或input檔案物件轉Base64字串
*
* Unit Test: {@link https://github.com/yuda-lyu/wsemi/blob/master/test/blob2b64.test.mjs Github}
* @memberOf wsemi
* @param {Blob|File} bb 輸入Blob或File
* @returns {Promise} 回傳Promise，resolve回傳Blob或File的Base64字串，reject回傳錯誤訊息
* @example
* need test in browser
*
* let b64 = 'YWJj5ris6Kmm'
* let u8a = b642u8arr(b64)
* let bb = new Blob([u8a])
* blob2b64(bb)
* .then(function(b64Out){
* console.log(b64Out)
* // => data:application/octet-stream;base64,YWJj5ris6Kmm
* })
*
*/
function blob2b64(bb) {
//pm
let pm = genPm()
//reader
let reader = new FileReader()
//onload
reader.onload = function () {
//resolve
pm.resolve(reader.result)
}
//onerror
reader.onerror = function (err) {
//reject
pm.reject(err)
}
//readAsDataURL
reader.readAsDataURL(bb)
return pm
}
export default blob2b64