parsing - 在 Rust 语言中将 String 解析为 Unsigned 的问题

Question

这是我的代码:

fn main() {
  use std::io::stdin;
  let mut s=String::new();
  stdin().read_line(&mut s).expect("Wrong input");
  let n = s.parse::<u32>();
  println!("Try: {:?}", n);
}

我在编译时没有出错，但它在运行时打印了这个:

Err(ParseIntError { kind: InvalidDigit })

Answer 1

您的字符串中有尾随 \n，请使用 String::trim_end :

fn main() {
  let n = "10\n".trim_end().parse::<u32>();
  println!("Try: {:?}", n);
}

来自 BufRead::read_line documentation :

This function will read bytes from the underlying stream until the newline delimiter (the 0xA byte) or EOF is found. Once found, all bytes up to, and including, the delimiter (if found) will be appended to buf.