主题：如何从一串文本中提取电话号码或手机号码？

一个不太严谨的做法（供参考）

Dim str As String  = "请请18012361955联系18012361956请联系 18012361953"
For i As Integer = 0 To str.Length -1
    Dim mn As Integer = 0
    Dim 电话 As String = ""   
    If str.IndexOf("1",i) > 1 Then
        If str.Length - 12 > 0 Then
            电话 = str.SubString(str.IndexOf("1",i) ,11)
            For n As Integer = 0 To 10
                If Char.IsDigit(电话.Chars(n)) = False Then     ‘检证11位数字
                    i = i + n
                    Exit For
                Else
                    mn = mn + 1
                    i = i + 1
                   
                End If
            Next
            If mn = 11 Then
            Output.Show(电话)
            End If
        End If
    End If
    If str.Length - i < 11   Then
        Exit For
    End If
Next