WebJul 11, 2024 · You can use the keyword is or switch over runtimeType : dynamic foo = 42; if (foo is int) { print ("Hello"); } switch (foo.runtimeType) { case int: { print ("World"); } } Consider using is instead of directly using runtimeType. As is works with subclasses. While using runtimeType is a strict comparison. Share Improve this answer Follow WebJul 9, 2024 · You can't do type checks using Type objects in Dart. A Type object is not the type, it's just a token representing the type which can be used with the dart:mirrors reflection library. It cannot, really, be used for anything else.
Dart Flutter: How to check the variable type is a String or not ...
WebJun 5, 2013 · Jun 5, 2013 at 21:55. You can write var a = new A (); int b = a; – SpiderPig. Jun 5, 2013 at 22:55. Implicit type conversion hard to implement in script langauge. But explicit conversion can be implemented very easy. Currrently in Dart not exists explicit conversion operator as such. So you cannot do this in Dart var a = (int) new A ... WebFeb 2, 2024 · There is a way to check whether one type is a subtype of another, and it does use the is operator, but you need to have an instance as the first operand and a type as the second. You can't just create an instance of an unknown type, so we instead rely in Dart's covariant generics: bool isSubtype () => [] is List; chukka boots men\u0027s extra wide width
dart - How to tell if an object is an instance of a class - Stack Overflow
WebFeb 25, 2024 · A Type object is a dumb token intended for use with dart:mirrors. All you can do to Type objects is to check if they refer to that same type. If you want to use it as a type (check if something is an instance of it, use it as a type argument), you need to pass the type as a type argument. WebDart also provides one way to check the type during run-time. is and is! operators are used to check the type of a variable in dart. For example : main(List args) { var value = 2; print(value is int); print(value is! … WebOften Dart’s control flow analysis can detect when a non-nullable variable is set to a non-null value before it’s used, but sometimes analysis fails. Two common cases are top-level variables and instance variables: Dart often can’t determine whether they’re set, so it … chukka boots men macys