Question

I am a long time C# developer and have had to look at some VB6 code lately. After some digging, we found out that, somewhere, somehow, we are storing a number as a string. Now we are reading it back and our code is not handling culture differences very well. Here is an example:

Dim text as String
Dim myVal as Double
Set text = "1,123456"
'This sets the value of myVal to 1123456 on our system - incorrect
myVal = text

Set text = "1.123456"
'This sets the value of myVal to 1.123456 on our system - correct
myVal = text

Keeping in mind that this is VB6 and NOT VB.NET, are there any built-in methods, functions, whatever, that can convert a string to a double using a particular culture?
Or at the very least, hinting to the conversion that we may be dealing with a different format?

We are still digging how the value gets written and see if we can reverse engineer the process to give us a consistent result. However, our customer(s) already has(have) data in one format or the other (or both, we are checking…), so a proper conversion algorithm or implementation would be a better answer at this point.

Answer 1

I’ve used this quick and dirty function in the past to get a double from a text. Here in Argentina, people sometimes use the point and sometimes the comma to separate decimal values, so this function is ready to accept both formats. If only one punctuation is present, it’s assumed that it’s the decimal separator.

function ConvertDBL( texto )
    dim retval, SepDecimal, SepMiles
    If texto = "" then texto = "0"
    retval = replace(trim(texto), " ", "")
    If cdbl("3,24") = 324 then
        SepDecimal = "."
        SepMiles = ","
    else
        SepDecimal = ","
        SepMiles = "."
    end if  
    If InStr( Retval, SepDecimal ) > 0 then
        If InStr( Retval, SepMiles ) > 0 then
            If InStr( Retval, SepDecimal ) > InStr( Retval, SepMiles ) then
                Retval = replace( Retval, SepMiles, "" )
            else
                Retval = replace( Retval, SepDecimal, "" )
                Retval = replace( Retval, SepMiles, SepDecimal )
            end if
        end if      
    else
        Retval = replace( Retval, SepMiles, SepDecimal )
    end if
    ConvertDbl = cdbl( retval ) 
end function