use std::fs::{self, OpenOptions};
use std::io::{Write, Read};fn main() {let file = std::fs::File::open("data.txt");println!("文件打开\n{:?}", file);let file = std::fs::File::create("data2.txt").expect("创建失败");println!("文件创建成功{:?}", file);fs::remove_file("data.txt").expect("无法删除文件");println!("文件已删除");let mut file = OpenOptions::new().append(true).open("data2.txt").expect("失败");// file.write("\nRust Programming Language".as_bytes()).expect("写入失败");// println!("\n数据追加成功");file.write_all("Rust".as_bytes()).expect("失败");file.write_all("\nRust".as_bytes()).expect("失败");println!("\n数据写入成功");// // write_all并不会在写入后自动写入换行\nlet mut file = std::fs::File::open("data2.txt").unwrap();let mut contents = String::new();file.read_to_string(&mut contents).unwrap();println!("{}", contents);
}