写流完成后如何返回承诺？

您将要使用

Promise

function writeToFile(filePath: string, arr: string[]): Promise<boolean> {  return new Promise((resolve, reject) => {    const file = fs.createWriteStream(filePath);    for (const row of arr) {      file.write(row + "n");    }    file.end();    file.on("finish", () => { resolve(true); }); // not sure why you want to pass a boolean    file.on("error", reject); // don't forget this!  });}