Dynamic Arrays

  • Maximum 4-dimensional arrays.
  • Declared with an unspecified first dimension (e.g., double matrix[][10][20];).
  • Compiler automatically creates a dynamic array object for correct initialization.
  • Automatically freed when exiting their block's visibility area.
  • Example: ArrayResize(matrix, 5); to set the first dimension size.
  • Static Arrays

  • All significant array dimensions are explicitly specified (e.g., double stat_array[5];).
  • Compiler pre-allocates the necessary memory.
  • A dynamic array object is associated with the static array's buffer for function parameter passing.
  • Example: some_function(stat_array); where some_function accepts double& array[].
  • Arrays in Structures

  • Static arrays declared as structure members do not create a dynamic array object by default (for Windows API compatibility).
  • Static arrays within structures can be passed to MQL5 functions.
  • When passed to MQL5 functions, a temporary dynamic array object is created, linked to the structure member.
  • Related Topics

  • [Array Functions](/array)
  • [Initialization of Variables](/basis/variables/initialization)
  • [Visibility Scope and Lifetime of Variables](/basis/variables/variable_scope)
  • [Creating and Deleting Objects](/basis/variables/object_live)