isValid method

Checks if Object has a valid value.

The following values are considered not valid:

• objects thats fail against a custom validation functions (if provided). The custom validation function must return a list of booleans. If at least one of the booleans is true, the object is considered valid.;
• NULL objects, independent of type;
• Strings that are empty, equal to "null" or have only white spaces;
• nums that are equal to 0;
• DateTimes that are equal to minDate;
• bools that are equal to false;
• Iterables that are empty or have only invalid values;
• Maps that are empty or have only invalid values;
• Classes that implement Validators that have validation errors;
• For other types, this method calls toString() and checks the result string against isValid.

Returns true if the Object is valid, false otherwise.

Example 1:

var value = "Hello";
var isValid = isValid(value);
print(isValid); // Output: true

Example 2:

var number = 0;
var isValidNumber = isValid(number);
print(isValidNumber); // Output: false

Example 3:

var date = DateTime.now();
var isValidDate = isValid(date);
print(isValidDate); // Output: true

Example 4:

var list = [1, 2, 3];
var isValidList = isValid(list);
print(isValidList); // Output: true

Example 5:

var map = {'name': 'John', 'age': 30};
var isValidMap = isValid(map);
print(isValidMap); // Output: true

Example 6:

class Person implements Validator {
 String name;
int age;
Person(this.name, this.age);
@override
List<String> validate() {
var errors = <String>[];
if (name.isEmpty) {
  errors.add('Name is required');
}
if (age <= 0) {
  errors.add('Age must be greater than 0');
}
 return errors;
}
}
var person = Person('John', 30);
var isValidPerson = isValid(person);
print(isValidPerson); // Output: true