std::time 只做时间戳、不做年月日。由第三方库(chrono)做
核心原因：日期太复杂，标准库不敢随便背锅
Duration
设置时间长度（间隔），通常用来延时等待、时间计算
new生成
new(秒, 纳秒)
use std::time::{SystemTime, Duration};fn main() {let d = Duration::new(1, 222);println!("d(秒)：{:?}", d);
}
d(秒)：1.000000222s
快速生成间隔
使用最多
from_secs和from_millis
use std::time::{Duration, Instant, SystemTime};fn main() {let s1 = Duration::from_secs(1); // 1秒let s2 = Duration::from_millis(1); // 1000毫秒 = 1秒let s3 = Duration::from_micros(1); // 1000微秒 = 1毫秒let s4 = Duration::from_nanos(1); // 1000纳秒 = 1微妙println!("s1: {:?}", s1);println!("s2: {:?}", s2);println!("s3: {:?}", s3);println!("s4: {:?}", s4);
}
s1: 1s
s2: 1ms
s3: 1µs
s4: 1ns
单位转换
use std::time::{Duration, Instant, SystemTime};fn main() {let s1 = Duration::from_secs(1); // 1秒println!("{:?}", s1.as_secs()); // 转秒println!("{:?}", s1.as_millis()); // 转毫秒println!("{:?}", s1.as_micros()); // 转微妙println!("{:?}", s1.as_nanos()); // 转纳秒
}
1
1000
1000000
1000000000
加减
注意时间不能为负数
use std::time::{Duration, Instant, SystemTime};fn main() {let s1 = Duration::from_secs(1); // 1秒let s2 = Duration::from_millis(233);let s3 = s1 + s2;println!("s3: {:?}", s3);// let s4 = s2 - s1;// println!("{:?}", s4);let s4 = s1 - s2;println!("s4: {:?}", s4);
}
s3: 1.233s
s4: 767ms
Instant
计时专用时间点（性能计时、超时、间隔）
now
-
Instant::now()：表示电脑开机到现在的秒数 + 纳秒
-
tv_sec: 秒
-
tv_nsec: 纳秒
-
use std::time::{Duration, Instant, SystemTime};
use std::thread::sleep;fn main() {let s1 = Instant::now();println!("s1: {:?}", s1);
}
s1: Instant { tv_sec: 868612, tv_nsec: 111540916 }
计算间隔
elapsed本质是Instant::now() - self
use std::time::{Duration, Instant, SystemTime};
use std::thread::sleep;fn main() {let s1 = Instant::now();// 睡眠2秒sleep(Duration::from_secs(2));// 返回Durationlet s2 = s1.elapsed();println!("s2: {:?}", s2);
}
s2: 2.0012385s
时间加减
Instant和Duration
- Instant(时间节点) + Duration(时长) = Instant(时间节点)
- Instant(时间节点) - Duration(时长) = Instant(时间节点)
use std::time::{Duration, Instant, SystemTime};fn main() {let s1 = Instant::now();let s2 = s1 + Duration::from_secs(1);println!("s2: {:?}", s2);
}
s2: Instant { tv_sec: 867631, tv_nsec: 79020083 }
Instant和Instant
- Instant(时间节点) - Instant(时间节点) =Duration(时长/间隔)
- 就是elapsed
Instant+Instant报错
use std::time::{Duration, Instant, SystemTime};
use std::thread::sleep;fn main() {let s1 = Instant::now();sleep(Duration::from_secs(1));let s2 = Instant::now();println!("d: {:?}", s2 - s1);
}
d: 1.005040791s
比较时间先后
use std::time::{Duration, Instant, SystemTime};fn main() {let s1 = Instant::now();let s2 = Instant::now();if s1 < s2 {println!("s1 is less than s2 ");} else {println!("s1 is not less than s2 ");}
}
s1 is less than s2
SystemTime
日历专用时间点
now
-
SystemTime::now()：表示1970-01-01 到现在的秒数 + 纳秒
-
tv_sec: 秒
-
tv_nsec: 纳秒
-
use std::time::{Duration, Instant, SystemTime};fn main() {let s1 = SystemTime::now();println!("s1: {:?}", s1);
}
s1: SystemTime { tv_sec: 1775747289, tv_nsec: 707167000 }
时差计算
SystemTime和Duration
- SystemTime(时间节点) + Duration(间隔) =SystemTime(时间节点)
- SystemTime - Duration =SystemTime
use std::time::{Duration, Instant, SystemTime};
use std::thread::sleep;fn main() {let s1 = SystemTime::now();// 加10秒let s2 = s1 + Duration::from_secs(10);println!("s1: {:?}", s1);println!("s2: {:?}", s2);
}
s1: SystemTime { tv_sec: 1775748144, tv_nsec: 473886000 }
s2: SystemTime { tv_sec: 1775748154, tv_nsec: 473886000 }
SystemTime和SystemTime
- SystemTime - SystemTime = Duration
- SystemTime + SystemTime报错
use std::time::{Duration, Instant, SystemTime};
use std::thread::sleep;fn main() {let s1 = SystemTime::now();sleep(Duration::from_secs(1));let s2 = SystemTime::now();// 相当于s2 - s1let s3 = s2.duration_since(s1).unwrap();println!("s3: {:?}", s3);
}
时间戳
SystemTime转时间戳
use std::time::SystemTime;fn main() {let time = SystemTime::now();// 转换成从1970-01-01开始的秒数// 等于SystemTime::now() - SystemTime::UNIX_EPOCHlet ts = time.duration_since(SystemTime::UNIX_EPOCH).unwrap();println!("时间戳：{}", ts.as_secs());
}
时间戳：1775748200
时间戳转SystemTime
use std::time::{SystemTime, Duration};fn main() {let t = "14135644000".parse().unwrap();let s = SystemTime::UNIX_EPOCH + Duration::from_secs(t);println!("时间戳(秒)：{:?}", s);
}
时间戳(秒)：SystemTime { tv_sec: 14135644000, tv_nsec: 0 }