CDbl
Converts numeric or string expression to `Double` precision floating point
Syntax
`
Declare Function CDbl ( ByVal expression As datatype ) As Double
Type typename
Declare Operator Cast ( ) As Double
End Type
`
Usage
`
result = CDbl( numeric expression )
result = CDbl( string expression )
result = CDbl( user defined type )
`
Parameters
`expression`
a numeric, string, or pointer expression to cast to a `Double` value
`datatype`
any numeric, string, or pointer data type
`typename`
a user defined type
Return Value
A `Double` precision value.
Description
The `CDbl` function returns a 64-bit `Double` value. The function does not check for an overflow, so be sure not to pass a value outside the representable range of the `Double` data type. The name can be explained as 'Convert to DouBLe'.
If the argument to `CDbl` is a string expression, it is first converted to numeric by using `Val`.
Example
`
' Using the CDBL function to convert a numeric value
'Create an DOUBLE variable
Dim numeric_value As Double
'Convert a numeric value
numeric_value = CDbl(-12345678.123)
'Print the result, should return -12345678.123
Print numeric_value
Sleep
`
Differences from QB

- The string argument was not allowed in QB

See also

- `CByte`
- `CUByte`
- `CShort`
- `CUShort`
- `CInt`
- `CUInt`
- `CLng`
- `CULng`
- `CLngInt`
- `CULngInt`
- `CSng`