从AlphaNumeric字符串中提取数字

Question

我有一个字母数字字符串，如sdff45hg589>@#DF456&<jk778P&&FHJ75，我只想提取数字，而不使用regex或任何其他函数。

Dim input As String = "sdff45hg589>@#DF456&<jk778P&&FHJ75"
Dim output As String = New String((From c As Char In input Select c Where Char.IsDigit(c)).ToArray())
MsgBox(output) 'Display the output 

消息框将显示4558945677875。

为了从同一个字符串中提取字母，我使用以下方法：

 Dim input As String =  "sdff45hg589>@#DF456&<jk778P&&FHJ75"
 Dim output As String = New String((From c As Char In input Select c Where Char.IsLetter(c)).ToArray())
 MsgBox (output)

这是提取两者的更好的方法吗？

Answer 1

如果您想同时提取这两个字符(我不知道这是否是一个要求，问题中不清楚)，您应该迭代每个字符一次，将它们放在不同的列表中。

  Dim input As String = "sdff45hg589>@#DF456&<jk778P&&FHJ75"
  Dim characters As List(Of Char) = New List(Of Char)()
  Dim numbers As List(Of Char) = New List(Of Char)()
  For Each c As Char In input
     If (Char.IsNumber(c)) Then
        numbers.Add(c)
     ElseIf (Char.IsLetter(c)) Then
        characters.Add(c)
     End If
  Next

'Do whatever you have to do here

编辑

正如@mjolka所指出的，由于用户的目标是显示分裂的数字和字母，所以使用StringBuilder更合适。这是我最新的答复：

  Dim input As String = "sdff45hg589>@#DF456&<jk778P&&FHJ75"
  Dim characters As StringBuilder = New StringBuilder()
  Dim numbers As StringBuilder = New StringBuilder()
  For Each c As Char In input
     If (Char.IsNumber(c)) Then
        numbers.Append(c)
     ElseIf (Char.IsLetter(c)) Then
        characters.Append(c)
     End If
  Next

'Do whatever you have to do here

Answer 2

您可以通过一个非常简单的regex替换来完成这一任务。

Dim match = Regex.Replace("sdff45hg589>@#DF456&<jk778P&&FHJ75", "\D", "")

非数字为"\D"，然后将其替换为空字符串。

我找了上面的数据