length property
Return the length of Array
Examples
var a1 = Array([1.0, 2.0, 3.0]);
print(a1.length);
/* output:
3
*/
Implementation
@override
int get length => l.length;
Setting the length
changes the number of elements in the list.
The list must be growable.
If newLength
is greater than current length,
new entries are initialized to null
,
so newLength
must not be greater than the current length
if the element type E
is non-nullable.
final maybeNumbers = <int?>[1, null, 3];
maybeNumbers.length = 5;
print(maybeNumbers); // [1, null, 3, null, null]
maybeNumbers.length = 2;
print(maybeNumbers); // [1, null]
final numbers = <int>[1, 2, 3];
numbers.length = 1;
print(numbers); // [1]
numbers.length = 5; // Throws, cannot add `null`s.
Implementation
@override
set length(int newLength) {
if (newLength < 0) {
throw FormatException(
'newLength must be greater equal than 0 (newLength >= 0)');
}
if (newLength == 0) {
l.clear();
} else if (newLength > l.length) {
for (var i = l.length; i < newLength; i++) {
l.add(0.0);
}
} else if (newLength < length) {
l.removeRange(newLength, l.length);
}
}