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Rust program to parse only time from a string

Rust | Date & Time Example: Write a program to parse only time from a string.
Submitted by Nidhi, on November 10, 2021

Problem Solution:

In this program, we will parse only time from string using parse_from_str() function and print the result.

Add Chrono date-time external library to your project

1. Create your project using the below command.
   

   $cargo new datetime -bin

2. Goto the project folder cd datetime and edit Cargo.toml file.
   

   $datetime>nano Cargo.toml

3. Then add dependency in Cargo.toml file
   

   [dependencies]
   chrono = "0.4"

4. After that, build your project using the below command
   

   $datetime>cargo build

5. Then execute your project after modification in src/main.rs source file.
   

   $datetime>cargo run

Program/Source Code:

The source code to parse only time from the string is given below. The given program is compiled and executed on UBUNTU 18.04 successfully.

// Rust program to parse only time 
// from string

use chrono::{DateTime, NaiveDate, NaiveDateTime, NaiveTime};
use chrono::format::ParseError;

fn main() -> Result<(), ParseError> {
    let time = NaiveTime::parse_from_str("22:45:24", "%H:%M:%S")?;
    println!("Time: {}", time);
    Ok(())
}

Output:

$datetime> cargo run
   Compiling datetime v0.1.0 (/home/arvind/Desktop/rust/datetime)
    Finished dev [unoptimized + debuginfo] target(s) in 0.34s
     Running `target/debug/datetime`

Time: 22:45:24

Explanation:

In the above program, we imported the "Chrono" library to our project for performing date and time operations. We imported the Chrono library using the below line:

use chrono::Utc;

In the main() function, we called NaiveTime::parse_from_str() function to parse the time string into time and print the result.

Rust Date and Time Programs »

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