我寫這門課
class Profile {
String email;
String password;
Profile({this.email, this.password});
}
但它說
"The parameter 'email' can't have a value of 'null' because of its type, but the implicit default value is 'null'.
Try adding either an explicit non-'null' default value or the 'required' modifier.dartmissing_default_value_for_parameter"
uj5u.com熱心網友回復：
通過添加必需的：
class Profile {
String email;
String password;
Profile({
required this.email,
required this.password,
});
}
通過添加可選：
class Profile {
String? email;
String? password;
Profile({
this.email,
this.password,
});
}
通過添加默認值：
class Profile {
String email;
String password;
Profile({
this.email = "[email protected]",
this.password = "123",
});
}
uj5u.com熱心網友回復：
你必須讓他們接受一個null價值。
class Profile {
String? email;
String? password;
Profile({this.email, this.password});
}
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