C# 如何处理;“无固定尺寸”;pinvoke结构中的数组?
您将如何用c#编写这种类型的结构 如果没有为C# 如何处理;“无固定尺寸”;pinvoke结构中的数组?,c#,arrays,struct,pinvoke,C#,Arrays,Struct,Pinvoke,您将如何用c#编写这种类型的结构 如果没有为ProcessIdList数组设置大小,您会怎么做?你是这样写的吗: [StructLayout(LayoutKind.Sequential)] struct JOBOBJECT_BASIC_PROCESS_ID_LIST { int NumberOfAssignedProcesses; int NumberOfProcessIdsInList; IntPtr ProcessIdList; //Must point to a allo
ProcessIdList
数组设置大小,您会怎么做?你是这样写的吗:
[StructLayout(LayoutKind.Sequential)]
struct JOBOBJECT_BASIC_PROCESS_ID_LIST
{
int NumberOfAssignedProcesses;
int NumberOfProcessIdsInList;
IntPtr ProcessIdList; //Must point to a allocated array, thanks jdweng for letting me know.
}
或者您是否只指定一个足够大的尺寸,例如:
[StructLayout(LayoutKind.Sequential)]
struct JOBOBJECT_BASIC_PROCESS_ID_LIST
{
int NumberOfAssignedProcesses;
int NumberOfProcessIdsInList;
[MarshalAs(UnmanagedType.ByValArray, SizeConst = MAX_PATH)]
UIntPtr[] ProcessIdList; //Works just fine, but is limited to the SizeConst.
}
我认为你提到的任何一种方法都应该奏效 此外,c#中还有一个匹配功能:使用fixed关键字定义数组:
struct JOBOBJECT_BASIC_PROCESS_ID_LIST
{
int NumberOfAssignedProcesses;
int NumberOfProcessIdsInList;
fixed IntPtr ProcessIdList[1];
}
见文件:
也没有边界检查,因此您应该能够轻松阅读struckt末尾后面的内容:
注
除了使用stackalloc创建的内存外,C#编译器和公共语言运行库(CLR)不执行任何安全缓冲区溢出检查。与所有不安全代码一样,请谨慎使用
通常会声明这种结构(例如,在WLan API中也有类似的结构):
你的第一种方法是正确的。您有一个32位指针。但是指针必须指向一个进程列表大小的已分配内存。内存必须在非托管内存中。哦,好的。我知道固定大小的缓冲区,但被告知使用它们是不明智的,所以我有点远离它们。如果您不介意回答另一个问题(与本问题不同),您会如何处理字符串,其中在结构中字段以
DWORD StrLength=>LPWSTR-Str=>DWORD-Attribute
的形式排列?这与数组(IntPtr
/fixed char[]
)是一样的吗?这是不正确的。非托管结构中的数组的要点是它可以容纳任意长度。@DavidHeffernan您没有对它进行边界检查。这意味着您可以访问x.ProcessIdList[2],即使数组大小定义为1。问问自己,如何使用长度大于1的数组声明这样的结构。只要别人声明了,它就好了,就像C++一样。但是你怎么用C语言声明这样的事情呢。考虑一下你实际回答的文本,“我认为你提到的任何一种方法都应该有效。”事实上,这两种方法中的两种方法都不能奏效。“DavidHeffernan我测试了这3种方法,而你对1种不可用的方法是正确的,第一种是用<代码>code>,你对第二个不正确,它工作得很好,因为它在技术上确实声明了新的uintpttr[MAX_PATH],唯一的缺点是,如果有超过260个进程ID,那么显然你将无法访问其他进程ID。这个答案中的一个不起作用,因为它基本上破坏了结构,而且你也不能做修复IntPtr
。我只接受了这个答案,因为这是唯一的答案,如果你能提供一个更好的,那么就去吧。
struct JOBOBJECT_BASIC_PROCESS_ID_LIST
{
int NumberOfAssignedProcesses;
int NumberOfProcessIdsInList;
fixed IntPtr ProcessIdList[1];
}
[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Auto)]
public struct JOBOBJECT_BASIC_PROCESS_ID_LIST
{
public int NumberOfAssignedProcesses;
public int NumberOfProcessIdsInList;
public IntPtr[] ProcessIdList;
public JOBOBJECT_BASIC_PROCESS_ID_LIST(IntPtr pList)
{
int nIntSize = Marshal.SizeOf<int>(); // 4
NumberOfAssignedProcesses = Marshal.ReadInt32(pList, 0);
NumberOfProcessIdsInList = Marshal.ReadInt32(pList, nIntSize);
ProcessIdList = new IntPtr[NumberOfProcessIdsInList];
for (int i = 0; i < NumberOfProcessIdsInList; i++)
{
IntPtr pItemList = IntPtr.Zero;
if (Marshal.SizeOf<IntPtr>() == 4)
pItemList = new IntPtr(pList.ToInt32() + (i * Marshal.SizeOf<IntPtr>()) + (nIntSize * 2));
else
pItemList = new IntPtr(pList.ToInt64() + (i * Marshal.SizeOf<IntPtr>()) + (nIntSize * 2));
IntPtr nPID = new IntPtr();
nPID = Marshal.ReadIntPtr(pItemList, 0);
ProcessIdList[i] = nPID;
}
}
}
private IntPtr hJob = IntPtr.Zero;
bool bRet = false;
hJob = CreateJobObject(IntPtr.Zero, "Test Job Object");
JOBOBJECT_EXTENDED_LIMIT_INFORMATION jbeli = new JOBOBJECT_EXTENDED_LIMIT_INFORMATION();
jbeli.BasicLimitInformation.LimitFlags |= (JOB_OBJECT_LIMIT_KILL_ON_JOB_CLOSE | JOB_OBJECT_LIMIT_SILENT_BREAKAWAY_OK | JOB_OBJECT_LIMIT_BREAKAWAY_OK);
int nLength = Marshal.SizeOf(typeof(JOBOBJECT_EXTENDED_LIMIT_INFORMATION));
IntPtr pJobInfo = Marshal.AllocHGlobal(nLength);
Marshal.StructureToPtr(jbeli, pJobInfo, false);
SetInformationJobObject(hJob, JOBOBJECTINFOCLASS.JobObjectExtendedLimitInformation, pJobInfo, (uint)nLength);
Marshal.FreeHGlobal(pJobInfo);
int nNbProcesses = 5;
for (int i = 0; i < nNbProcesses; i++)
{
using (Process exeProcess = new Process())
{
exeProcess.StartInfo.FileName = "notepad";
exeProcess.Start();
exeProcess.WaitForInputIdle();
IntPtr hProcess = exeProcess.Handle;
bRet = AssignProcessToJobObject(hJob, hProcess);
}
}
JOBOBJECT_BASIC_PROCESS_ID_LIST jobpil = new JOBOBJECT_BASIC_PROCESS_ID_LIST();
jobpil.NumberOfAssignedProcesses = nNbProcesses;
int nSize = Marshal.SizeOf<JOBOBJECT_BASIC_PROCESS_ID_LIST>() + (nNbProcesses - 1) * Marshal.SizeOf<IntPtr>();
IntPtr pJobpil = Marshal.AllocHGlobal(nSize);
Marshal.StructureToPtr(jobpil, pJobpil, false);
int nReturnLength = 0;
bRet = QueryInformationJobObject(hJob, JOBOBJECTINFOCLASS.JobObjectBasicProcessIdList, pJobpil, nSize, out nReturnLength);
if (bRet)
{
var processidlist = new JOBOBJECT_BASIC_PROCESS_ID_LIST(pJobpil);
foreach (var pid in processidlist.ProcessIdList)
{
Console.WriteLine("PID: {0}", pid.ToString());
}
}
else
{
int nErr = Marshal.GetLastWin32Error();
Win32Exception win32Exception = new Win32Exception(nErr);
this.Activate();
MessageBox.Show("Error: " + win32Exception.Message, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
Marshal.FreeHGlobal(pJobpil);
// CloseHandle can be added in Form1_FormClosed :
private void Form1_FormClosed(object sender, FormClosedEventArgs e)
{
CloseHandle(hJob);
}
[DllImport("Kernel32.dll", SetLastError = true, CharSet = CharSet.Unicode)]
public static extern IntPtr CreateJobObject(IntPtr lpJobAttributes, string lpName);
[DllImport("Kernel32.dll", SetLastError = true, CharSet = CharSet.Unicode)]
public static extern bool SetInformationJobObject(IntPtr hJob, JOBOBJECTINFOCLASS JobObjectInfoClass, IntPtr lpJobObjectInfo, uint cbJobObjectInfoLength);
[DllImport("Kernel32.dll", SetLastError = true, CharSet = CharSet.Unicode)]
public static extern bool AssignProcessToJobObject(IntPtr hJob, IntPtr hProcess);
[DllImport("Kernel32.dll", SetLastError = true, CharSet = CharSet.Unicode)]
public static extern bool CloseHandle(IntPtr hObject);
[DllImport("Kernel32.dll", SetLastError = true, CharSet = CharSet.Unicode)]
public static extern bool QueryInformationJobObject(IntPtr hJob, JOBOBJECTINFOCLASS JobObjectInformationClass, [Out, MarshalAs(UnmanagedType.SysUInt)] IntPtr lpJobObjectInformation, int cbJobObjectInformationLength, out int lpReturnLength);
[StructLayout(LayoutKind.Sequential)]
struct JOBOBJECT_BASIC_LIMIT_INFORMATION
{
public ulong PerProcessUserTimeLimit;
public ulong PerJobUserTimeLimit;
public int LimitFlags;
public IntPtr MinimumWorkingSetSize;
public IntPtr MaximumWorkingSetSize;
public int ActiveProcessLimit;
public IntPtr Affinity;
public int PriorityClass;
public int SchedulingClass;
}
[StructLayout(LayoutKind.Sequential)]
struct IO_COUNTERS
{
public ulong ReadOperationCount;
public ulong WriteOperationCount;
public ulong OtherOperationCount;
public ulong ReadTransferCount;
public ulong WriteTransferCount;
public ulong OtherTransferCount;
}
[StructLayout(LayoutKind.Sequential)]
struct JOBOBJECT_EXTENDED_LIMIT_INFORMATION
{
public JOBOBJECT_BASIC_LIMIT_INFORMATION BasicLimitInformation;
public IO_COUNTERS IoInfo;
public IntPtr ProcessMemoryLimit;
public IntPtr JobMemoryLimit;
public IntPtr PeakProcessMemoryUsed;
public IntPtr PeakJobMemoryUsed;
}
//
// Basic Limits
//
public const int JOB_OBJECT_LIMIT_WORKINGSET = 0x00000001;
public const int JOB_OBJECT_LIMIT_PROCESS_TIME = 0x00000002;
public const int JOB_OBJECT_LIMIT_JOB_TIME = 0x00000004;
public const int JOB_OBJECT_LIMIT_ACTIVE_PROCESS = 0x00000008;
public const int JOB_OBJECT_LIMIT_AFFINITY = 0x00000010;
public const int JOB_OBJECT_LIMIT_PRIORITY_CLASS = 0x00000020;
public const int JOB_OBJECT_LIMIT_PRESERVE_JOB_TIME = 0x00000040;
public const int JOB_OBJECT_LIMIT_SCHEDULING_CLASS = 0x00000080;
//
// Extended Limits
//
public const int JOB_OBJECT_LIMIT_PROCESS_MEMORY = 0x00000100;
public const int JOB_OBJECT_LIMIT_JOB_MEMORY = 0x00000200;
public const int JOB_OBJECT_LIMIT_JOB_MEMORY_HIGH = JOB_OBJECT_LIMIT_JOB_MEMORY;
public const int JOB_OBJECT_LIMIT_DIE_ON_UNHANDLED_EXCEPTION = 0x00000400;
public const int JOB_OBJECT_LIMIT_BREAKAWAY_OK = 0x00000800;
public const int JOB_OBJECT_LIMIT_SILENT_BREAKAWAY_OK = 0x00001000;
public const int JOB_OBJECT_LIMIT_KILL_ON_JOB_CLOSE = 0x00002000;
public const int JOB_OBJECT_LIMIT_SUBSET_AFFINITY = 0x00004000;
public const int JOB_OBJECT_LIMIT_JOB_MEMORY_LOW = 0x00008000;
public enum JOBOBJECTINFOCLASS
{
JobObjectBasicAccountingInformation = 1,
JobObjectBasicLimitInformation,
JobObjectBasicProcessIdList,
JobObjectBasicUIRestrictions,
JobObjectSecurityLimitInformation, // deprecated
JobObjectEndOfJobTimeInformation,
JobObjectAssociateCompletionPortInformation,
JobObjectBasicAndIoAccountingInformation,
JobObjectExtendedLimitInformation,
JobObjectJobSetInformation,
JobObjectGroupInformation,
JobObjectNotificationLimitInformation,
JobObjectLimitViolationInformation,
JobObjectGroupInformationEx,
JobObjectCpuRateControlInformation,
JobObjectCompletionFilter,
JobObjectCompletionCounter,
JobObjectReserved1Information = 18,
JobObjectReserved2Information,
JobObjectReserved3Information,
JobObjectReserved4Information,
JobObjectReserved5Information,
JobObjectReserved6Information,
JobObjectReserved7Information,
JobObjectReserved8Information,
JobObjectReserved9Information,
JobObjectReserved10Information,
JobObjectReserved11Information,
JobObjectReserved12Information,
JobObjectReserved13Information,
JobObjectReserved14Information = 31,
JobObjectNetRateControlInformation,
JobObjectNotificationLimitInformation2,
JobObjectLimitViolationInformation2,
JobObjectCreateSilo,
JobObjectSiloBasicInformation,
JobObjectReserved15Information = 37,
JobObjectReserved16Information,
JobObjectReserved17Information,
JobObjectReserved18Information,
JobObjectReserved19Information = 41,
JobObjectReserved20Information,
MaxJobObjectInfoClass
}