VB & VBA in a Nutshell: The Language

CDbl Function

Named Arguments

No

Syntax

CDbl(expression)

expression

Use: Required

Data Type: Numeric or String

–1.79769313486232E308 to –4.94065645841247E-324 for negative values; 4.94065645841247E-324 to 1.79769313486232E308 for positive values.

Return Value

expression cast as a Double data type.

Description

Converts expression to a Double data type.

Rules at a Glance

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

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

Example

Dim dblMyNumber as Double
If IsNumeric(sMyNumber) then
    dblMyNumber = CDbl(sMyNumber)
End If

Programming Tips and Gotchas

• When converting a string representation of a number to a numeric, you should use the data type conversion functions—such as CDbl—instead of Val, because the data type conversion functions take account of the system's regional settings. While CDbl recognizes and handles the thousands separator, the Val function can't. If a user inputs a value of 6,231,532.11, for example, CDbl correctly converts it to a double with a value of 6231532.11, while Val returns a value of 6.

• Use IsNumeric to test whether expression evaluates to a number.

See Also

FormatNumberFunction, IsNumeric Function, Val Function