Question

I have tried a couple different ways and cannot seem to get the result I want using vb.net.

I have an array of strings. {“55555 “,”44444″, ” “}

I need an array of integers {55555,44444}

This is a wpf page that is sending the array as a parameter to a crystal report.

Any help is appreciated.

Answer 1

You can use the List(Of T).ConvertAll method:

Dim stringList = {"123", "456", "789"}.ToList
Dim intList = stringList.ConvertAll(Function(str) Int32.Parse(str))

or with the delegate

Dim intList = stringList.ConvertAll(AddressOf Int32.Parse)

If you only want to use Arrays, you can use the Array.ConvertAll method:

Dim stringArray = {"123", "456", "789"}
Dim intArray = Array.ConvertAll(stringArray, Function(str) Int32.Parse(str))

Oh, i’ve missed the empty string in your sample data. Then you need to check this:

Dim value As Int32
Dim intArray = (From str In stringArray
               Let isInt = Int32.TryParse(str, value)
               Where isInt
               Select Int32.Parse(str)).ToArray

By the way, here’s the same in method syntax, ugly as always in VB.NET:

Dim intArray = Array.ConvertAll(stringArray,
                        Function(str) New With {
                            .IsInt = Int32.TryParse(str, value),
                            .Value = value
                        }).Where(Function(result) result.IsInt).
                Select(Function(result) result.Value).ToArray