list of integer to comma delimited string

Question

I have tried this several ways and keep getting an error each time I try.

This is using .net 3.5 with asp.net(forms) and vb.net.

Examples:

Dim _registrations = New List(Of Integer)

Dim regList As String

Dim ListOfReg = _registrations.convertall(Of String)(Function(i As Integer) i.ToString())

regList = String.Join(",", ListOfReg.ToArray())

Error message:

Overload resolution failed because no Public 'convertall' can be called with these arguments: 'Public Function ConvertAll(Of String)(converter As System.Converter(Of Integer,String)) As System.Collections.Generic.List(Of String)': Argument matching parameter 'converter' cannot convert from 'VB$AnonymousDelegate_0(Of Integer,String)' to 'Converter(Of Integer,String)'.

Other attempt:

regList = String.Join(",", (_registrations.Select(Function(reg) reg.ToString()).ToArray()))

Error message:

Public member 'Select' on type 'List(Of Integer)' not found.

Any help is appreciated.

Thanks.

Answer 1

this should work , I guess it is the square brackets on the select?

.NET 3.5 solution

Dim integers As List(Of Integer) = New List(Of Integer)
integers.Add(1)
integers.Add(2)
integers.Add(3)

Dim commas As String = String.Join(",", integers.[Select](Function(i) i.ToString()).ToArray())

MessageBox.Show(commas)

Below is the.NET 4.0 Solution

Dim integers As List(Of Integer) = New List(Of Integer)
        integers.Add(1)
        integers.Add(2)
        integers.Add(3)


        Dim commas As String = String.Join(",", integers.ToArray)

        MessageBox.Show(commas)