VB.NET Language in a Nutshell, Second Edition

Name

CInt Function

Named Arguments

No

Syntax

CInt(expression)

expression (required; Numeric or String)

The range of expression is -2,147,483,648 to 2,147,483,647; fractions are rounded.

Return Value

expression cast as an Integer

Description

Converts expression to an Integer; any fractional portion of expression is rounded.

Rules at a Glance

• expression must evaluate to a numeric value; otherwise, a type-mismatch error is generated.

• If the value of expression is outside the range of the Integer data type, an overflow error is generated.

• When the fractional part of expression is exactly .5, CInt always rounds it to the nearest even number. For example, .5 rounds to 0, and 1.5 rounds to 2.

Example

Dim iMyNumber as Integer
If IsNumeric(sMyNumber) then
    iMyNumber = CInt(sMyNumber)
End If

Programming Tips and Gotchas

• When converting a string representation of a number to a numeric data type, you should use the data type conversion functions — such as CInt — instead of Val, because the data type conversion functions take into account the system’s regional settings. In particular, CInt recognizes the thousands separator if it’s present in expression, whereas Val does not. For example, if expression is 1,234, then CInt successfully converts it to the integer value 1234, while Val converts it to 1.

• Use IsNumeric to test whether expression evaluates to a number before performing the conversion.

• CInt differs from the Fix and Int functions, which truncate, rather than round, the fractional part of ...