![]() ![]() ![]() *The LongLong and LongPtr data types were added in VBA7. Null character repeated for length of string The Variant data type can be used to hold almost any type of data, however it is more efficient, more descriptive, and more secure to assign a specific data type for each variable and function. Each data type takes up a certain amount of memory, has a certain range of values, and has a default value representing the falsey value for the type. If you are defining a class or structure and you need to control the storage layout of its members, you can apply the StructLayoutAttribute attribute to the class or structure.Īn Object referring to any elementary or composite data type uses 4 bytes in addition to the data contained in the data type.Data Types define what kinds of values can be stored in a variable or returned from a function. You cannot even make assumptions about byte alignment, such as a 2-byte or 4-byte boundary. You cannot safely assume that the order of storage in memory is the same as your order of declaration. On a 64-bit platform this requirement is doubled. Visual basic data types plus#On a 32-bit platform, this overhead is currently 12 bytes plus 8 bytes for each dimension. For example, an array uses extra memory for the array itself and also for each dimension. Some composite types have additional memory requirements. Furthermore, there are other considerations, such as the following: You cannot rely on simply adding together the nominal storage allocations of the type's members. The same considerations apply to each member of a composite data type, such as a structure or an array. ![]() Storage assignment on a 64-bit platform is different from assignment on a 32-bit platform. In other cases it might align their memory addresses to natural hardware boundaries to optimize performance. If memory is nearly full, it might pack your declared elements as closely together as possible. The common language runtime can assign storage based on the current characteristics of the platform on which your application is executing. This is due to the following considerations: When you declare an elementary data type, it is not safe to assume that its memory consumption is the same as its nominal storage allocation. In addition to specifying a data type in a declaration statement, you can force the data type of some programming elements by using a type character. So 3.56E+2 signifies 3.56 x 10 2 or 356, and 3.56E-2 signifies 3.56 / 10 2 or 0.0356.įor strings containing text, use the StrConv function to convert from one text format to another. † In scientific notation, "E" refers to a power of 10. 3.4028235E+38 through -1.401298E-45 † for negative values 1.401298E-45 through 3.4028235E+38 † for positive valuesĠ to approximately 2 billion Unicode charactersĠ through 18,446,744,073,709,551,615 (1.8.E+19 †) (unsigned)Įach member of the structure has a range determined by its data type and independent of the ranges of the other members The following table shows the Visual Basic data types, their supporting common language runtime types, their nominal storage allocation, and their value ranges. ![]()
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