Unhandled Exception: type 'String' is not a subtype of type 'int' of 'index' flutter new - flutter

Question

I am not getting output on my app and it should have give a output like many question is how to sisplay json data in my flutter app
class AppState extends State<AppName>{
var name ;
var email ;
int cgpa ;
TextEditingController user = new TextEditingController();
String url = 'http://10.42.0.243:8000/students/';
getData(String username) async{
String profile = url+'?search='+username;
var res = await http.get(profile,headers: {"Accept":"application/json"});
print(res.body);
debugPrint(res.body);
var resBody = json.decode(res.body);
name = resBody['sname'].toString();
email = resBody['email'].toString();
cgpa = resBody['cgpa'] ;
debugPrint(name);
setState(() {
print("Success");
});
}
my app screenshot is
JSON Data Screenshot
Error output:
Performing hot reload...
Syncing files to device Moto G 5 Plus...
Reloaded 0 of 576 libraries in 389ms.
E/BpSurfaceComposerClient(28411): Failed to transact (-1)
E/BpSurfaceComposerClient(28411): Failed to transact (-1)
I/flutter (28411): [{"id":1,"sname":"Ashutosh Lokhande","email":"2016bit053#sggs.ac.in","year":"2016","cgpa":7.2}]
I/flutter (28411): [{"id":1,"sname":"Ashutosh Lokhande","email":"2016bit053#sggs.ac.in","year":"2016","cgpa":7.2}]
E/flutter (28411): [ERROR:flutter/lib/ui/ui_dart_state.cc(148)] Unhandled Exception: type 'String' is not a subtype of type 'int' of 'index'
E/flutter (28411): #0 AppState.getData (package:json_flutter/main.dart:28:19)
E/flutter (28411):
E/flutter (28411): #1 AppState.build. (package:json_flutter/main.dart:56:34)
E/flutter (28411): #2 _InkResponseState._handleTap (package:flutter/src/material/ink_well.dart:654:14)
E/flutter (28411): #3 _InkResponseState.build. (package:flutter/src/material/ink_well.dart:729:32)
E/flutter (28411): #4 GestureRecognizer.invokeCallback (package:flutter/src/gestures/recognizer.dart:182:24)
E/flutter (28411): #5 TapGestureRecognizer._checkUp (package:flutter/src/gestures/tap.dart:365:11)
E/flutter (28411): #6 TapGestureRecognizer.handlePrimaryPointer (package:flutter/src/gestures/tap.dart:275:7)
E/flutter (28411): #7 PrimaryPointerGestureRecognizer.handleEvent (package:flutter/src/gestures/recognizer.dart:455:9)
E/flutter (28411): #8 PointerRouter._dispatch (package:flutter/src/gestures/pointer_router.dart:75:13)
E/flutter (28411): #9 PointerRouter.route (package:flutter/src/gestures/pointer_router.dart:102:11)
E/flutter (28411): #10 GestureBinding.handleEvent (package:flutter/src/gestures/binding.dart:218:19)
E/flutter (28411): #11 GestureBinding.dispatchEvent (package:flutter/src/gestures/binding.dart:198:22)
E/flutter (28411): #12 GestureBinding._handlePointerEvent (package:flutter/src/gestures/binding.dart:156:7)
E/flutter (28411): #13 GestureBinding._flushPointerEventQueue (package:flutter/src/gestures/binding.dart:102:7)
E/flutter (28411): #14 GestureBinding._handlePointerDataPacket (package:flutter/src/gestures/binding.dart:86:7)
E/flutter (28411): #15 _rootRunUnary (dart:async/zone.dart:1136:13)
E/flutter (28411): #16 _CustomZone.runUnary (dart:async/zone.dart:1029:19)
E/flutter (28411): #17 _CustomZone.runUnaryGuarded (dart:async/zone.dart:931:7)
E/flutter (28411): #18 _invoke1 (dart:ui/hooks.dart:263:10)
E/flutter (28411): #19 _dispatchPointerDataPacket (dart:ui/hooks.dart:172:5)
E/flutter (28411):