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stringvb.netlisttypesdouble

Converting a List of String to List of Double without losing information (VB.net)

I got a List of String. I am losing information (the dot) when I try to convert an entry to type Double. What am I doing wrong?

 Dim list As New List(Of String)
 Dim a As Double

 list.Add("309.69686")
 a = CDbl(list(0))
 MsgBox(a)
'Output: 30969686
Solution

  • This happens because in your locale the separator for decimal numbers is probably not a point but something else (usually a comma).
    You are using the old VB6 methods to convert this string to a double and this method (CDbl) has no way to use a different locale settings.

    So in the most basic form you need to change that method to the native .NET methods

    a = Double.Parse(list(0), CultureInfo.InvariantCulture)

    Here we pass the information about what locale setting Parse should use in converting the input string to a double. And the InvariantCulture uses the point as separator.

    Of course, you should consider that, if the input string is obtained from the user input, then you could face other problems (like invalid numeric strings). In this case you should not use double.Parse, but double.TryParse