javascript - 如何使用 chrome 应用程序文件系统将 FileEntry 转换为标准的 JavaScript 文件对象

Question

是否可以将 FileEntry 转换为标准的 JavaScript 对象 File？ 我在文档中找不到任何有意义的内容 https://developer.chrome.com/apps/fileSystem

Answer 1

FileEntry documentation确实在此处提供指导:

The FileSystemFileEntry interface of the File System API represents a file in a file system. It offers properties describing the file's attributes, as well as the file() method, which creates a File object that can be used to read the file.

不幸的是，file()方法依赖于回调而不是 Promises，但我们可以包装它并使使用 API(和阅读代码)更容易:

async function getFile(fileEntry) {
  try {
    return new Promise((resolve, reject) => fileEntry.file(resolve, reject));
  } catch (err) {
    console.log(err);
  }
}

// From inside an async method or JS module
let file = await getFile(fileEntry); // Wait until we have the file