獲取當前計算機所有性能計數器

獲取本機所有計數器項目下面所有的實例，和註冊的計數器，並輸出到文件。

下面是代碼。

    Public Sub GetInf(Optional outputFile As String = "D:\pctext.txt")
        Dim f = File.Create(outputFile)
        Dim tw As New StreamWriter(f)
        For Each item As PerformanceCounterCategory In PerformanceCounterCategory.GetCategories()
            tw.WriteLine($"■■■■■■■■■■■■：{item.CategoryName.ToString()}")
            Dim insts() As String = item.GetInstanceNames()
            tw.WriteLine("♦♦♦：本機實例")
            If insts.Length > 0 Then
                For Each i In insts
                    tw.WriteLine($"|：{i}")
                Next
            Else
                tw.WriteLine("♦：沒有命名本機實例。")
            End If
            tw.WriteLine("♦♦♦：本機計數器")
            For Each ctor In item.GetCounters(If(insts.Length > 0, insts(0), ""))
                tw.WriteLine($"|：{ctor.CounterName}")
            Next
            tw.WriteLine("========================================")

        Next
        tw.Flush()
        f.Close()
        MsgBox("已完成。")
    End Sub