dart 函数练习

import 'dart:convert';
import 'dart:html';
 
void main() {
_getIPAddress() {
 
  final url = 'https://httpbin.org/ip';
 
  HttpRequest.request(url).then((value) {
 
      print(json.decode(value.responseText)['origin']);
 
  }).catchError((error) => print(error));
 
}
  _getIPAddress();
}

114.92.6.153, 114.92.6.153

async

import 'dart:convert';
import 'dart:html';
 
void main() {
_getIPAddress() async {
 
  final url = 'https://httpbin.org/ip';
 
  var request = await HttpRequest.request(url);
 
  String ip = json.decode(request.responseText)['origin'];
 
  print(ip);
 
}
  _getIPAddress();
}