The json tag

[:json var_name=a_Dart_expression]

Generates a JSON string by evaluating the given Dart expression and serializing it into a JSON string by use of JSON.encode.

For example, assume you have a variable as follows

result = ["john", "mike"];


[:json data={"users": result}]

will generates the following to the HTML output:

<script id="data" type="text/plain">{"users": ["john", "mike"]};</script>

To retrieve it in Dart (running at the browser), you can do as follows:

import 'dart:convert' show JSON;

void main() {
void server(Map<String, List<String>> data) {

To generate a JavaScript object that can be used by third-party JavaScript library, please use [:json-js] instead.

Notice: JSON is used to convert between String and Dart objects, so you have to make sure it can be serialized into a JSON string. For instance, you have to implement a method called toJson for your own classes.