php file:
$email=$_POST['email'];
$passworda=$_POST['passworda'];
$sql="SELECT * FROM user WHERE email='".$email."'AND passworda='".$password."' ";
$result=mysqli_query($db,$sql);
$count=mysqli_num_rows($result);
if($count>=1){
echo json_encode("success");
}
else
{
echo json_encode("error");
}
Login page Flutter:
class Login extends StatelessWidget {
TextEditingController email = TextEditingController();
TextEditingController password = TextEditingController();
Future login(BuildContext cont) async {
if (email.text == "" || password.text == "") {
Fluttertoast.showToast(
msg: "please complete!",
toastLength: Toast.LENGTH_SHORT,
gravity: ToastGravity.CENTER,
fontSize: 16.0,
);
} else {
var url = "http://192.168.43.150/v1_flutter/lib/php/connection.php";
var response = await http.post(Uri.parse(url), body: {
"email": email.text,
"pass": password.text,
}, headers: {"Accept":"applicarion/json"});
var data = jsonDecode(response.body);
if (data == "success") {
Navigator.pop(cont);
Navigator.pushNamed(cont, "/registre");
} else {
Fluttertoast.showToast(
msg: "The user and password does not exist!",
toastLength: Toast.LENGTH_SHORT,
gravity: ToastGravity.CENTER,
fontSize: 16.0,
);
}
}}
Console:
E/flutter (6084): [Error: flutter/lib/ui/ui_dart_state.cc(198)] Unhandled exception: FormatException: Unexpected character (at Character 1) E/Flutter (6084):
E/Flutter(6084):^ E/Flutter(6084): E/Flutter(6084): #0 _ChunkedJsonParser.fail (dart:convert-patch/convert_patch.dart:1383:5) E/Flutter(6084): #1 _ChunkedJsonParser.parseNumber (dart:convert-patch/convert_patch.dart:1250:9) E/Flutter(6084): #2 _ChunkedJsonParser.parse (dart:convert-patch/convert_patch.dart:915:22) E/Flutter(6084): #3 _parseJson (dart:convert-patch/convert_patch.dart:35:10) E/Flutter (6084): #4 JsonDecoder.convert (dart:convert/json.dart:612:36) E/Flutter (6084): #5 JsonCodec.decode (dart:convert/json.dart:216:41) E/Flutter (6084): #6 jsonDecode (dart:convert/json.dart:155:10) E/Flutter (6084): #7 Login.login (package:mes_v1/pages/Authentification/login.dart:25:18) E/Flutter(6084): E/Flutter(6084):
![[Web front-end] Node.js quick start](https://img.php.cn/upload/course/000/000/067/662b5d34ba7c0227.png)
Your code does look error-prone, but focusing on your question: the exception looks clear and your response parsing is breaking. (I would also say that you should wrap your code with try/catch to prevent any code breaking and catch issues properly).
Let us solve your problem:
var data = jsonDecode(response.body);This will convert your string (response.body) to json, which means
datais aMaporList (where dynamic is a Map or another nested list), so the following doesn't make any sense if(data=="success"){Now, let's take a look at your php code:
echo json_encode("Success");I'm not a php expert, but from the documentation it should be used like this:
$response = array("result" => "Success"); echo json_encode($response);Now let’s get back to your dart code:
var success = false; try{ final baseUrl = "http://192.168.43.150"; // Use final wherever you can final url = "$baseUrl/v1_flutter/lib/php/connection.php"; // Improving flexibility final body ={
"email": email.text,
"pass": password.text,
}; // Decouple in variables for readability
final headers = {"Accept":"application/json"}; // Fix typo
final response = await http.post(Uri.parse(url), body: body, headers: headers);
final data = jsonDecode(response.body);
success = data["result"] == "Success";
} catch(e) {
print("Catched an error!");
print(e);
success = false;
}
if(success) {
...