Parsing and serializing JSON
JSON is a widely used data interchange format. It is a human-readable, but also easily machine-readable.
To parse a JSON string, you can use the builtin JSON.parse function. The value is returned as a JavaScript object.
const text=`{ "hello": "world", "numbers": [1, 2, 3]}`;const data=JSON.parse(text);console.log(data.hello);console.log(data.numbers.length);To turn a JavaScript object into a JSON string, you can use the builtin JSON.stringify function.
const obj={hello:"world",numbers:[1,2,3],};const json=JSON.stringify(obj);console.log(json);// {"hello":"world","numbers":[1,2,3]}By default JSON.stringify will output a minified JSON string. You can customize this by specifying an indentation number in the third argument.
const json2=JSON.stringify(obj,null,2);console.log(json2);// {// "hello": "world",// "numbers": [// 1,// 2,// 3// ]// }Runthis example locally using the Deno CLI:
deno run https://docs.deno.com/examples/scripts/parsing_serializing_json.ts