Difference between CDec and CDbl

[James]

Can anyone explain the difference between these two conversion
functions? Thanks

 

[Herfried K. Wagner [MVP]]

Can anyone explain the difference between these two conversion
functions?

They convert to different types.

 

[Josip Medved]

One converts to Decimal, other to Double?

Can anyone explain the difference between these two conversion
functions? Thanks

 

[James]

i meant the technical differences... what does one read that the other
cannot? Thanks.

 

[Josip Medved]

i meant the technical differences... what does one read that the other

cannot? Thanks.

Since both decimal as double are numeric types, I doubt that there is
any difference, as in from what they can convert, but there is big
difference in types to which they convert to.

 

[Jay B. Harlow [MVP - Outlook]]

In addition to the other comments:

CDec returns a Decimal value.

CDbl returns Double value.

As you may know TypeOf Decimal IsNot TypeOf Double. Decimal is a base 10
floating point number, while Double is a base 2 floating point number. They
have different precisions & ranges.

If you have Option Strict On (you do have Option Strict On don't you)
attempting to use CDbl and assign it to a Decimal will cause a compile
error. While attempting to use CDec and assign it to a Double will cause an
implicit conversion from Decimal to Double (read it will work, but you
really did CDbl(CDec(?)).

 

[James]

As you may know TypeOf Decimal IsNot TypeOf Double. Decimal is a base 10

floating point number, while Double is a base 2 floating point number. They
have different precisions & ranges.

Can you explain this a little more? I work well with examples and I
don't really understand what you're saying here. Thanks!

 

[Jay B. Harlow [MVP - Outlook]]

Binary floating point & .NET:
http://www.yoda.arachsys.com/csharp/floatingpoint.html

Decimal floating point in .NET:
http://www.yoda.arachsys.com/csharp/decimal.html

The short of it is a Decimal number can exactly represent base 10 (ergo
Decimal) numbers. Double (and Single) cannot exactly represent base 10
numbers, as they store the numbers as base 2.