語言

PerformanceCounterCategory.GetInstanceNames 方法

定義

擷取與此類別相關聯的效能物件實例清單。

public:
 cli::array <System::String ^> ^ GetInstanceNames();
public string[] GetInstanceNames();
member this.GetInstanceNames : unit -> string[]
Public Function GetInstanceNames () As String()

傳回

String[]

一組字串陣列代表與此類別相關的效能物件實例名稱;若類別僅包含一個效能物件實例,則為單項陣列,包含空字串(“”)。

例外狀況

IsEditable 屬性為 true。 屬性可能尚未設定。

-或-

該類別沒有相關的實例。

基礎系統 API 的呼叫失敗。

未取得管理權限執行的程式碼嘗試讀取效能計數器。

範例

以下程式碼範例會得到一個物件清單PerformanceCounter。PerformanceCounterCategory 它會先根據是否指定計算機名稱,使用適當的建構函式來建立 PerformanceCounterCategory 物件。 接著它會將 GetInstanceNames 實例名稱以陣列 String的形式回傳,並進行排序與顯示。

public static void Main(string[] args)
{
    string categoryName = "";
    string machineName = "";
    PerformanceCounterCategory pcc;
    string[] instances;

    // Copy the supplied arguments into the local variables.
    try
    {
        categoryName = args[0];
        machineName = args[1]=="."? "": args[1];
    }
    catch
    {
        // Ignore the exception from non-supplied arguments.
    }

    try
    {
        // Create the appropriate PerformanceCounterCategory object.
        if (machineName.Length>0)
        {
            pcc = new PerformanceCounterCategory(categoryName, machineName);
        }
        else
        {
            pcc = new PerformanceCounterCategory(categoryName);
        }

        // Get the instances associated with this category.
        instances = pcc.GetInstanceNames();
    }
    catch(Exception ex)
    {
        Console.WriteLine("Unable to get instance information for " +
            "category \"{0}\" on " +
            (machineName.Length>0? "computer \"{1}\":": "this computer:"),
            categoryName, machineName);
        Console.WriteLine(ex.Message);
        return;
    }

    //If an empty array is returned, the category has a single instance.
    if (instances.Length==0)
    {
        Console.WriteLine("Category \"{0}\" on " +
            (machineName.Length>0? "computer \"{1}\"": "this computer") +
            " is single-instance.", pcc.CategoryName, pcc.MachineName);
    }
    else
    {
        // Otherwise, display the instances.
        Console.WriteLine("These instances exist in category \"{0}\" on " +
            (machineName.Length>0? "computer \"{1}\".": "this computer:"),
            pcc.CategoryName, pcc.MachineName);

        Array.Sort(instances);
        int objX;
        for(objX=0; objX<instances.Length; objX++)
        {
            Console.WriteLine("{0,4} - {1}", objX+1, instances[objX]);
        }
    }
}
Sub Main(ByVal args() As String)
    Dim categoryName As String = ""
    Dim machineName As String = ""
    Dim pcc As PerformanceCounterCategory
    Dim instances() As String

    ' Copy the supplied arguments into the local variables.
    Try
        categoryName = args(0)
        machineName = IIf(args(1) = ".", "", args(1))
    Catch ex As Exception
        ' Ignore the exception from non-supplied arguments.
    End Try

    Try
        ' Create the appropriate PerformanceCounterCategory object.
        If machineName.Length > 0 Then
            pcc = New PerformanceCounterCategory(categoryName, machineName)
        Else
            pcc = New PerformanceCounterCategory(categoryName)
        End If

        ' Get the instances associated with this category.
        instances = pcc.GetInstanceNames()

    Catch ex As Exception
        Console.WriteLine("Unable to get instance information for " & _
             "category ""{0}"" on " & IIf(machineName.Length > 0, _
             "computer ""{1}"":", "this computer:"), _
             categoryName, machineName)
        Console.WriteLine(ex.Message)
        Return
    End Try

    'If an empty array is returned, the category has a single instance.
    If instances.Length = 0 Then
        Console.WriteLine( _
            "Category ""{0}"" on " & IIf(machineName.Length > 0, _
            "computer ""{1}""", "this computer") & _
            " is single-instance.", pcc.CategoryName, pcc.MachineName)
    Else
        ' Otherwise, display the instances.
        Console.WriteLine( _
            "These instances exist in category ""{0}"" on " & _
            IIf(machineName.Length > 0, _
                "computer ""{1}"".", "this computer:"), _
            pcc.CategoryName, pcc.MachineName)

        Array.Sort(instances)
        Dim objX As Integer
        For objX = 0 To instances.Length - 1
            Console.WriteLine("{0,4} - {1}", objX + 1, instances(objX))
        Next objX
    End If
End Sub

備註

Note

要讀取 Windows Vista 及以後版本、Windows XP Professional x64 版或 Windows Server 2003 中非互動式登入會話的效能計數器,您必須是效能監控使用者群組的成員或擁有管理員權限。

若要避免提高許可權以存取 Windows Vista 和更新版本中的性能計數器,請將您自己新增至性能監視器使用者群組。

在 Windows Vista 和更新版本中,用戶帳戶控制 (UAC) 會決定用戶的許可權。 如果你是內建管理員群組的成員,你會被分配兩個執行時存取權杖:一個標準使用者存取權杖和一個管理員存取權杖。 根據預設,您處於標準使用者角色。 要執行存取效能計數器的程式碼,你必須先將權限從標準使用者提升為管理員。 當您以滑鼠右鍵按下應用程式圖示,並指出您想要以系統管理員身分執行,即可啟動應用程式。

適用於

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