Why I'm getting this error: The argument type 'String' can't be assigned to the parameter type 'int'?

Question

如果用户输入了错误的电子邮件和密码，这是状态代码和正文的响应。 I/flutter (20074): 200 I/flutter (20074): {"code":1,"message":"invalid username or password","data":null} 如果用户输入正确的电子邮件和密码，这就是响应 I/flutter (20074): 200 I/flutter (20074): {"code":0,"message":"success","data":{"Id":121106,"Name":"User 1","Email":"user@gmail.com","Token":"2db0ce86-2dc0-4381-97de-ce6e0c341d90"}}。如果用户输入了错误的电子邮件和密码，我想验证我的登录。它将显示“无效凭据”并且不会转到另一个页面。我的问题是，当我将此 response.body['code'] == 0 添加到我的 if 语句时，我得到了这个错误 The argument type 'String' can't be assigned to the parameter type 'int'。我该如何解决这个问题？

创建调用登录的函数postapi

Future<void> login() async {
    if(emailController.text.isNotEmpty && passController.text.isNotEmpty) {
      var headers =  {"Content-type": "application/json"};
      var myBody = {
        'email' : emailController.text,
        'password' : passController.text,
      };
      var response = await http.post(Uri.parse("url"),
          headers: headers,
          body: jsonEncode( myBody ));
      
      if(response.statusCode == 200 && response.body['code'] == 0) {
        Navigator.push(
            context,
            MaterialPageRoute(builder: (context) => const SecondRoute()));
      } else {
        ScaffoldMessenger.of(context).showSnackBar(const SnackBar(content: Text("Invalid Credentials.")));
      }
    } else {
      ScaffoldMessenger.of(context).showSnackBar(const SnackBar(content: Text("Blank Field Not Allowed")));
    }
  }

Answer 1

对象response.body是一个字符串。要访问响应中的单个对象，您首先需要解码 json.

var response = await http.post(Uri.parse("url"),
  headers: headers,
  body: jsonEncode( myBody ));
final data = json.decode(response.body);
if (response.statusCode == 200 && data['code'] == 0) {
  ...
}

Why I'm getting this error: The argument type 'String' can't be assigned to the parameter type 'int'?

Why I'm getting this error: The argument type 'String' can't be assigned to the parameter type 'int'?

android-studio

flutter