PerformanceCounterCategory.GetInstanceNames 方法
定义
重要
一些信息与预发行产品相关，相应产品在发行之前可能会进行重大修改。 对于此处提供的信息，Microsoft 不作任何明示或暗示的担保。
检索与此类别关联的性能对象实例列表。
public:
cli::array <System::String ^> ^ GetInstanceNames();public string[] GetInstanceNames ();member this.GetInstanceNames : unit -> string[]Public Function GetInstanceNames () As String()返回
String[]
字符串的数组，这些字符串表示与此类别关联的性能对象实例名称；或者，如果该类别仅包含一个性能对象实例，则为包含空字符串 ("") 的单项数组。
例外
对基础系统 API 的调用失败。
以不具有管理特权的用户身份正在执行的代码尝试读取性能计数器。
示例
下面的代码示例获取 中 PerformanceCounterCategory对象的列表PerformanceCounter。 它首先根据是否指定了计算机名称，使用适当的构造函数创建 PerformanceCounterCategory 对象。 然后，它使用 GetInstanceNames 将实例名称作为 的数组 String返回，它对其进行排序和显示。
public:
static void Main(array<String^>^ args)
{
String^ categoryName = "";
String^ machineName = "";
PerformanceCounterCategory^ pcc;
array<String^>^ instances;
// Copy the supplied arguments into the local variables.
try
{
categoryName = args[1];
machineName = args[2]=="."? "": args[2];
}
catch (...)
{
// Ignore the exception from non-supplied arguments.
}
try
{
// Create the appropriate PerformanceCounterCategory object.
if (machineName->Length > 0)
{
pcc = gcnew PerformanceCounterCategory(categoryName, machineName);
}
else
{
pcc = gcnew 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]);
}
}
}
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
注解
注意
若要从 Windows Vista 及更高版本、Windows XP Professional x64 Edition 或 Windows Server 2003 中的非交互式登录会话读取性能计数器，你必须是 性能监视器 用户组的成员或具有管理权限。
若要避免在 Windows Vista 及更高版本中提升访问性能计数器的权限，请将自己添加到性能监视器用户组。
在 Windows Vista 或更高版本中，用户帐户控制 (UAC) 决定用户的特权。 如果您是内置的 Administrators 组的成员，将为您分配两个运行时访问令牌：一个标准用户访问令牌和一个管理员访问令牌。 默认情况下，您拥有标准用户角色。 若要执行访问性能计数器的代码，必须先将特权从标准用户提升为管理员。 你可以通过以下方式执行此操作：右键单击应用程序图标并指示需以管理员身份运行。
