A very commonly used collection in programming is an array. Dart represents arrays in the form of List objects. A List is simply an ordered group of objects. The dart:core library provides the List class that enables creation and manipulation of lists
Lists can be of
- Fixed Length List
- Growable List
Fixed Length List
A fixed length list’s length cannot change at runtime
Declaring a list
Syntax
var list_name = new List(initial_size)
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The above syntax creates a list of the specified size. The list cannot grow or shrink at runtime. Any attempt to resize the list will result in an exception
Initializing a list
Syntax
Example
void main() {
var lst = new List(3);
lst[0] = 12;
lst[1] = 13;
lst[2] = 11;
print(lst);
}
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Output
Growable List
A growable list’s length can change at run-time
Example
void main() {
var num_list = [1,2,3];
print(num_list);
}
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Output
The following example creates a zero-length list using the empty List() constructor. The add() function in the List class is used to dynamically add elements to the list
void main() {
var lst = new List();
lst.add(1);
lst.add(2);
print(lst);
}
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Output
List Properties
The following table lists some commonly used properties of the List class in the dart:core library.
Sr.No |
Methods & Description |
1 |
first
Returns the first element case.
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2 |
isEmpty
Returns true if the collection has no elements.
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3 |
isNotEmpty
Returns true if the collection has at least one element.
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4 |
length
Returns the size of the list.
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5 |
last
Returns the last element in the list.
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6 |
reversed
Returns an iterable object containing the lists values in the reverse order.
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7 |
single
Checks if the list has only one element and returns it.
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