import { safeData } from './base.js';
/**
* @module index
* @author linjielinlin 993353454@qq.com
* @date 2022-05-11 22:07:43
* @description 文件相关处理
*/
/**
* @function blobToBase64
* @description 将Blob对象转换为base64字符串
* @date 2020-03-01
* @param {Blob} argBlob 需要处理的Blob对象
* @returns {Promise} 返回base64字符串
* @example
* blobToBase64(blob).then(base64 => console.log(base64));
*/
const blobToBase64 = async (argBlob) => {
return new Promise(function (resolve, reject) {
const fileReader = new FileReader();
fileReader.readAsDataURL(argBlob);
fileReader.onload = (e) => {
return resolve(e?.target?.result);
};
fileReader.onerror = () => {
return reject(new Error('文件流异常'));
};
});
};
/**
* @function blobUrlToFile
* @description 将blobUrl转换为File对象
* @date 2020-03-01
* @param {string} argData blobUrl
* @returns {Promise} 返回File对象
* @example
* blobUrlToFile(url).then(file => console.log(file));
*/
const blobUrlToFile = async (argData) => {
return new Promise(function (resolve, reject) {
// eslint-disable-next-line no-undef
var xhr = new XMLHttpRequest();
xhr.open('GET', argData, true);
xhr.responseType = 'blob';
xhr.onload = function (e) {
if (this.status === 200) {
return resolve(this.response);
}
};
xhr.onerror = (err) => {
return reject(err);
};
xhr.send();
});
};
/**
* @function dataURLtoBlob
* @description 将图片的dataUrl base64转换为Blob对象
* @param {string} argData dataUrl
* @returns {Blob} 返回Blob对象
* @example
* const blob = dataURLtoBlob(dataUrl);
*/
const dataURLtoBlob = (argData) => {
if (!argData.match(/;base64,/)) {
return new Blob();
}
let arr = argData.split(',');
let mime = safeData(arr[0].match(/:(.*?);/), '1', '');
if (!mime) {
return new Blob();
}
let bstr = globalThis.atob(arr[1]);
let n = bstr.length;
let u8arr = new Uint8Array(n);
while (n--) {
u8arr[n] = bstr.charCodeAt(n);
}
return new Blob([u8arr], { type: mime });
};
/**
* @function blobToFile
* @description 将Blob对象转换为File对象
* @param {Blob} argBlob Blob对象
* @param {string} argName 文件名，默认为当前时间戳
* @returns {File} 返回File对象
* @example
* const file = blobToFile(blob, 'example.txt');
*/
const blobToFile = (argBlob, argName = Date.now().toString()) => {
let file = new File([argBlob], argName, {
type: argBlob.type,
});
return file;
};
/**
* @function dlFile
* @description 下载文件
* @param {string|Blob|File} argData Blob对象/File对象/dataUrl/base64
* @param {string} argName 文件名
* @param {number} argDelTime 移除dateUrl时间
* @example
* dlFile(data, 'example.txt', 10000);
*/
const dlFile = (argData, argName = Date.now().toString(), argDelTime = 10000) => {
let downNode = globalThis.document.createElement('a');
downNode.download = argName;
// 字符内容转换为blob地址
let href = '';
if (typeof argData === 'string') {
if (argData.startsWith('blob:')) {
href = argData;
}
else if (argData.startsWith('data:')) {
href = argData;
}
argData = new Blob([argData]);
}
href = href || URL.createObjectURL(argData);
downNode.href = href;
setTimeout(() => {
URL.revokeObjectURL(href);
}, argDelTime);
globalThis.document.body.appendChild(downNode);
downNode.click();
globalThis.document.body.removeChild(downNode);
};
/**
* @function getDuration
* @description 获取音视频文件的时长
* @param {Blob|File|string} argFile 音视频数据，如果是string类型，则为链接
* @returns {Promise} 返回时长（单位：秒）
* @example
* getDuration(file).then(duration => console.log(duration));
*/
const getDuration = async (argFile) => {
let filePath;
if (typeof argFile === 'string') {
filePath = argFile;
}
else {
filePath = URL.createObjectURL(argFile);
}
return new Promise((resolve, reject) => {
const audio = new Audio(filePath);
audio.addEventListener('loadedmetadata', function (e) {
if (filePath.startsWith('blob:')) {
URL.revokeObjectURL(filePath);
}
const duration = audio.duration;
audio.src = '';
return resolve(duration);
});
setTimeout(() => {
return reject(new Error('读取时长超时'));
}, 5000);
});
};
/**
* @function loadFile
* @description 动态加载html文件标签
* @param {string} argUrl 要加载的url
* @param {string} argType 加载类型 js/css
* @param {object} argOptions
* @param {string} argOption.disCheck 不检查是否有相同标签
* @param {string} argOption.force 是否强制添加，true时先删除再添加
* @return {Promise} 返回Promise对象
* @example
* loadFile(url, 'js', {force: true}).then(() => console.log('Loaded'));
*/
const loadFile = (argUrl, argType = 'js', argOptions = {}) => {
let temId = argType + '-' + argUrl.split('/').pop();
let head = globalThis.document.getElementsByTagName('head')[0];
let nodeTag;
if (!argOptions.disCheck) {
let checkTag = globalThis.document.getElementById(temId);
// 已经存在对应tag
if (checkTag) {
if (argOptions.force) {
head.removeChild(checkTag);
}
else {
return Promise.resolve({ msg: '已存在，中断加载！' });
}
}
}
switch (argType) {
case 'css':
nodeTag = globalThis.document.createElement('link');
nodeTag.type = 'text/css';
nodeTag.rel = 'stylesheet';
nodeTag.href = argUrl;
break;
case 'js':
nodeTag = globalThis.document.createElement('script');
nodeTag.src = argUrl;
nodeTag.type = 'text/javascript';
break;
default:
console.error('暂不支持：' + argType);
return Promise.reject({ msg: '暂不支持：' + argType });
}
nodeTag.id = temId;
head.appendChild(nodeTag);
return new Promise((resolve) => {
if (nodeTag.readyState) {
nodeTag.onreadystatechange = function () {
if (nodeTag.readyState === 'complete') {
nodeTag.onreadystatechange = null;
return resolve(argUrl);
}
};
}
else {
// Others
nodeTag.onload = function () {
return resolve(argUrl);
};
}
});
};
export { blobToBase64, blobToFile, blobUrlToFile, dataURLtoBlob, dlFile, getDuration, loadFile };