VB data types

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Go back to: Visual Basic.Net resources => VB syntax For further information look in the VB.Net Help system under Data Type Summary

Data Types in VB.Net

Visual Basic has several different data types available for storing different sorts of data values. It is important that data is stored in the correct type of variable.

Main data types

Data can be divided into two main groupings:

  • Numeric data - which can be used to perform calculations
  • Non-numeric data - such as names, addresses, etc

In general, the distinction is simple - if the data value is a number then it is numeric data. But this does not always work, there are times when it is better to store some numbers as non-numeric values.

If in doubt - ask yourself: Will I want to perform calculations on this value?

  • If Yes - then use a numeric variable.
  • If No - then use a non-numeric variable.
What sort of data is a telephone number?
 e.g. 01902 321234
The number is made up of digits, but would you ever want (for example) to double it?

Numeric Data Types

Numeric data is again divided into two groupings:

  • Integers (whole numbers) e.g. 1, 0, -12
  • Real numbers (numbers with decimal points) e.g. 1.4, -12.36, 0.0

Each grouping has several data types, depending on the range of values to be stored. In general, the larger the numbers to be stored, the more memory is needed for the variable. We try to use the smallest data type which will hold our expected range of values.

Integer Data Types

Include:

  • Int - the standard integer data type, holds values in the range: -2,147,483,648 through to 2,147,483,647