rustHow to parse JSON string in Rust?

Parsing JSON string in Rust can be done using the serde crate. serde is a powerful library for serializing and deserializing data structures.

Example code

extern crate serde;
extern crate serde_json;

use serde_json::{Result, Value};

fn main() {
    // Some JSON input data as a &str. Maybe this comes from the user.
    let data = r#"
        {
            "name": "John Doe",
            "age": 43,
            "phones": [
                "+44 1234567",
                "+44 2345678"
            ]
        }"#;

    // Parse the string of data into serde_json::Value.
    let v: Value = serde_json::from_str(data)?;

    // Access parts of the data by indexing with square brackets.
    println!("Please call {} at the number {}", v["name"], v["phones"][0]);
}

Output example

Please call John Doe at the number +44 1234567

Code explanation

1. extern crate serde; and extern crate serde_json;: These two lines are used to import the serde and serde_json crates.

2. use serde_json::{Result, Value};: This line imports the Result and Value types from the serde_json crate.

3. let data = r#" ... "#;: This line creates a string literal containing the JSON data.

4. let v: Value = serde_json::from_str(data)?;: This line parses the JSON data into a Value type.

5. println!("Please call {} at the number {}", v["name"], v["phones"][0]);: This line prints out the parsed data.

Helpful links

• serde
• serde_json

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