rust 逐行读取文本文件

use std::fs::File;
use std::io::{BufRead, BufReader};

fn main() {

    //要打开的文件名
    let filename = "src/main.rs";
    //以只读模式打开文件
    let file = File::open(filename).unwrap();
    let lines = BufReader::new(file).lines();

    //遍历所有行
    for line in lines{
        if let Ok(data) = line {
            println!("{}", data);
        }
    }

}