亲们，问一下 如何给文件的开头添加内容？
一个已经存在的文件，里头有内容，但我想从文件开头添加内容，该怎么去添加.
9 回复
let stream = fs.createReadStream('a.txt')
stream.unshift(Buffer.from('添加内容'))
这样行不？
var path = require('path');
var fs = require('mz/fs');
async function appendFileHeadAsync(filepath, head) {
if (!await fs.exists(filepath)) throw new Error("file not exist!!");
var new_file_path = path.format({
root: '/ignored',
name: path.parse(filepath).name + "_n",
ext: path.parse(filepath).ext
});
await fs.writeFile(new_file_path, Buffer.concat([
Buffer.from(head, "utf8"),
await fs.readFile(filepath, {
"encoding": null
})
]), {
"encoding": "utf8",
"flag": "w"
});
await fs.unlink(filepath);
await fs.rename(new_file_path, filepath);
return true;
}
appendFileHeadAsync(path.join(__dirname, 'a/test13333.txt'), "hello node js \r\n").then(a => {
console.dir("success");
}).catch(err => {
console.dir(err);
});
let stream = fs.createReadStream('a.txt')
stream.unshift(Buffer.from('添加内容'))
stream.pipe(fs.createWriteStream('b.txt'))
@zhoujinhai 这样写回去就行了 godghdai 那个好些，封装成方法了，有验证
