环境
- Time 2022-01-12
- Rust 1.57.0
- Tokio 1.15.0
概念
参考:https://docs.rs/tokio/latest/tokio/fs/struct.File.html
示例
读取一行
use tokio::fs::File;
use tokio::io::{AsyncBufReadExt, BufReader};
#[tokio::main]
async fn main() -> std::io::Result<()> {
let file = File::open("test.txt").await?;
let mut reader = BufReader::new(file);
let mut buffer = String::new();
reader.read_line(&mut buffer).await?;
println!("{}", buffer);
Ok(())
}
循环读取行
use tokio::fs::File;
use tokio::io::{AsyncBufReadExt, BufReader};
#[tokio::main]
async fn main() -> std::io::Result<()> {
let file = File::open("test.txt").await?;
let mut lines = BufReader::new(file).lines();
while let Some(line) = lines.next_line().await? {
println!("{}", line);
}
Ok(())
}
全部读取
use tokio::fs::read_to_string;
#[tokio::main]
async fn main() -> std::io::Result<()> {
let content = read_to_string("test.txt").await?;
println!("{}", content);
Ok(())
}
总结
Tokio 对于读取文件,也可以使用异步的方式。