Solidity Tutorial: all about Array
10 min readDec 25, 2019
In Solidity, an array
is an ordered list of items that is indexed numerically, starting at 0.
Array types
In this section, we provide two types of categorisation for arrays:
- Fixed-size vs dynamic size arrays
- One-dimensional vs Multi-Dimensional arrays.
Fixed-size vs Dynamic-Size array
The Solidity documentation make the distinction between fixed-size and dynamic size arrays. In the examples below, T
is the element type and k
is the array length / size. If k = 5
, the array can hold a maximum of 5 values.
- Fixed Size:
T[k]
// array that can hold 5 unsigned integers maximumuint[5] my_array;
- Dynamic Size:
T[]
// array containing an undefined number of stringsstring[] my_array;
One Dimensional vs Multi-Dimensional arrays
One Dimensional and Multi-Dimensional arrays can be both of Fixed-Size or Dynamic-Size. The One Dimensional arrays are essentially the examples cited above. Here are the definitions
T[k]
: One Dimensional, Fixed-sizeT[]
: One…