Data Types
Data Types define the type of data that a variable can store. Some variables store numbers, others store names. The built-in VB.NET type aliases and their equivalent .NET Framework types follow:
Integers
VB Alias | .NET Type | Size | Range |
SByte | System.SByte | 8 bits (1 byte) | -128 to 127 |
Byte | System.Byte | 8 bits (1 byte) | 0 to 255 |
Short | System.Int16 | 16 bits (2 bytes) | -32,768 to 32,767 |
UShort | System.UInt16 | 16 bits (2 bytes) | 0 to 65,535 |
Integer | System.Int32 | 32 bits (4 bytes) | -2,147,483,648 to 2,147,483,647 |
UInteger | System.UInt32 | 32 bits (4 bytes) | 0 to 4,294,967,295 |
Long | System.Int64 | 64 bits (8 bytes) | -9,223,372,036,854,775,808 to 9,223,372,036,854,775,807 |
ULong | System.UInt64 | 64 bits (8 bytes) | 0 to 18,446,744,073,709,551,615 |
Floating-point
VB Alias | .NET Type | Size | Precision | Range |
Single | System.Single | 32 bits (4 bytes) | 7 digits | 1.5 x 10-45 to 3.4 x 1038 |
Double | System.Double | 64 bits (8 bytes) | 15-16 digits | 5.0 x 10-324 to 1.7 x 10308 |
Decimal | System.Decimal | 128 bits (16 bytes) | 28-29 decimal places | 1.0 x 10-28 to 7.9 x 1028 |
Other pre-defined types
VB Alias | .NET Type | Size (bits) | Range |
Char | System.Char | 16 bits (2 bytes) | One Unicode symbol in the range of 0 to 65,535. |
Boolean | System.Boolean | 32 bits (4 bytes) | True or False |
Object | System.Object | 32/64 bits (4/8 bytes) | Platform dependent (a reference to an object). |
Date | System.DateTime | 64 bits (8 bytes) | January 1, 0001 12:00:00 AM to December 31, 9999 11:59:59 PM |
String | System.String | 80 + [16 * Length] bits (10 + [2 * Length] bytes) | A Unicode string with a maximum length of 2,147,483,647 characters. |
Value Types
· All numeric data types
· Boolean, Char, and Date
· All structures, even if their members are reference types
· Enumerations, since their underlying type is always SByte, Short, Integer, Long, Byte, UShort, UInteger, orULong
Reference Types
· String
· All arrays, even if their elements are value types
· Class types, such as Form
· Delegates
Elements That Are Not Types
· Namespaces
· Modules
· Events
· Properties and procedures
· Variables, constants, and fields
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