Dart and Flutter data types
One of the most fundamental features of a programming language is the set of data types it supports. These are the types of data that can be represented and manipulated in a programming language.
Dart has special support for the following data types:
- lists (also known as arrays)
You can initialize an object of any of these special types using a literal. For example,
'this is a string' is a
string literal and
true is a
Since all variables in Dart refer to an
object - an instance of a class - you can often use constructors to initialize variables.
Some of the built-in types have their own builders. For example, you can use the
Map() builder to create a map.
Dart data types
64-bit floating point numbers (double precision) as specified by the IEEE 754 standard.
The int and double are subtypes of num. The num type includes basic operators like +, -, / and *, and is also where you’ll find abs (), ceil () and floor (), among other methods.
A String is a sequence of UTF-16 code units. You can use single or double quotation marks to create a string.
To represent boolean values, Dart has a type called bool. Only two objects have bool type: true and false boolean literals, which are constants at compile time.
Perhaps the most common collection in almost all programming languages is the array or ordered group of objects. In Dart, arrays are List objects.
A Dart Set is an unordered collection of unique items. Dart support for sets is provided by set literals and by set type.
In general, a map is an object that associates keys and values. Keys and values can be any type of object.
Each key occurs only once, but you can use the same value multiple times.