環境

• Time 2022-01-12
• Rust 1.57.0
• Tokio 1.15.0

概念

參考：https://docs.rs/tokio/latest/tokio/fs/struct.File.html

示例

main.rs

use tokio::{fs::File, io::AsyncWriteExt};

#[tokio::main]
async fn main() {
    let mut file = File::create("test.txt").await.unwrap();
    file.write_all(b"jiangbo").await.unwrap();
    println!("寫入完成");
}
 

快取寫入

use tokio::fs::File;
use tokio::io::{AsyncWriteExt, BufWriter};

#[tokio::main]
async fn main() {
    let file = File::create("test.txt").await.unwrap();
    let mut writer = BufWriter::new(file);
    writer.write_all(b"jiangbo").await.unwrap();
    writer.flush().await.unwrap();
    println!("寫入完成");
}
 

追加

use tokio::fs::{File, OpenOptions};
use tokio::io::{AsyncWriteExt, BufWriter};

#[tokio::main]
async fn main() -> std::io::Result<()> {
    let file = File::create("test.txt").await?;
    let mut writer = BufWriter::new(file);
    writer.write_all(b"jiangbo").await?;
    writer.flush().await?;
    println!("寫入完成");

    let file = OpenOptions::new().append(true).open("test.txt").await?;
    let mut writer = BufWriter::new(file);
    writer.write_all("\n測試追加".as_bytes()).await?;
    writer.flush().await?;
    println!("追加完成");

    Ok(())
}
 

總結

Tokio 對於寫入檔案，也可以使用非同步的方式。

附錄