asp.net - 整数列表到逗号分隔的字符串

Question

我已经尝试了几种方法，每次尝试都会出错。

这是将 .net 3.5 与 asp.net(forms) 和 vb.net 一起使用。

例子:

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())

错误信息:
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)'.
其他尝试:

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

错误信息:
Public member 'Select' on type 'List(Of Integer)' not found.
任何帮助表示赞赏。

谢谢。

Answer 1

这应该有效，我猜是选择上的方括号？

.NET 3.5 解决方案

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)

下面是.NET 4.0解决方案

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)