VB 获取系统内存信息

可以获取的内存信息:
- 物理内存大小
- 可用物理内存
- 物理内存占用率
- 页面内存总大小
- 可用页面内存
- 页面内存占用率
- 页面内存池大小
- 非页面内存池大小
- 虚拟内存大小
- 可用虚拟内存
- 虚拟内存占用率

代码如下(模块):

Option Explicit
Private Declare Function NtQueryInformationProcess Lib "ntdll.dll" (ByVal ProcessHandle As Long, ByVal ProcessInformationClass As Long, ByVal ProcessInformation As Long, ByVal ProcessInformationLength As Long, ByRef ReturnLength As Long) As Long
Private Declare Function NtQuerySystemInformation Lib "ntdll.dll" (ByVal SystemInformationClass As Long, ByVal SystemInformation As Long, ByVal SystemInformationLength As Long, ByRef ReturnLength As Long) As Long

Private Type LARGE_INTEGER
    LowPart As Long
    HighPart As Long
End Type

Private Type PROCESS_QUOTA_LIMITS
  PagedPoolLimit As Long
  NonPagedPoolLimit As Long
  MinimumWorkingSetSize As Long
  MaximumWorkingSetSize As Long
  PagefileLimit As Long
  TimeLimit As LARGE_INTEGER
  Unknown As Long
End Type

Private Type SYSTEM_BASIC_INFORMATION
   Reserved As Long
   TimerResolution As Long
   PageSize As Long
   NumberOfPhysicalPages As Long
   LowestPhysicalPage As Long
   HighestPhysicalPage As Long
   AllocationGranularity As Long
   MinimumUserModeAddress As Long
   MaximumUserModeAddress As Long
   ActiveProcessorsAffinityMask As Long
   NumberOfProcessors As Byte
End Type

Private Type VM_COUNTERS
    PeakVirtualSize As Long
    VirtualSize As Long
    PageFaultCount As Long
    PeakWorkingSetSize As Long
    WorkingSetSize As Long
    QuotaPeakPagedPoolUsage As Long
    QuotaPagedPoolUsage As Long
    QuotaPeakNonPagedPoolUsage As Long
    QuotaNonPagedPoolUsage As Long
    PagefileUsage As Long
    PeakPagefileUsage As Long
End Type

Public Type MEMORY_USAGE
  LoadedMemory As Long "物理内存占用率
  PhysicalMemorySize As Currency "物理内存大小
  AvailablePhysicalMemory As Currency "可用物理内存
  PagedPoolSize As Currency "页面内存池大小
  NonPagedPoolSize As Currency "非页面内存池大小
  PagefileMemorySize As Currency "页面内存大小
  AvailablePagefileMemory As Currency "可用页面内存大小
  VirtualMemorySize As Currency "虚拟内存大小(一般为2GB)
  AvailableVirtualMemory As Currency "可用虚拟内存
End Type

Public Function GetMemoryUsage(MemoryUsage As MEMORY_USAGE) As Long
  Dim BasicInfo As SYSTEM_BASIC_INFORMATION
  Dim QuotaLimits As PROCESS_QUOTA_LIMITS
  Dim Vm As VM_COUNTERS
  Dim PerInfo(77) As Long
  Dim Status As Long
  Dim ReturnLength As Long
  Dim ProcessAPagefile As Currency
  Dim SystemAPagefile As Currency

  Status = NtQuerySystemInformation(0, ByVal VarPtr(BasicInfo), LenB(BasicInfo), 0)
  If Status Then Exit Function
  Status = NtQuerySystemInformation(2, ByVal VarPtr(PerInfo(0)), 312, 0)
  If Status Then Exit Function
  Status = NtQueryInformationProcess(-1, 1, ByVal VarPtr(QuotaLimits), Len(QuotaLimits), ReturnLength)
  Status = NtQueryInformationProcess(-1, 3, ByVal VarPtr(Vm), LenB(Vm), 0)

  If PerInfo(11) < 100 Then
    MemoryUsage.LoadedMemory = 100
  Else
    MemoryUsage.LoadedMemory = Fix((BasicInfo.NumberOfPhysicalPages - PerInfo(11)) * 100 / BasicInfo.NumberOfPhysicalPages)
  End If
  MemoryUsage.PhysicalMemorySize = CCur(BasicInfo.NumberOfPhysicalPages) * BasicInfo.PageSize
  MemoryUsage.AvailablePhysicalMemory = CCur(PerInfo(11)) * BasicInfo.PageSize
  MemoryUsage.PagedPoolSize = CCur(PerInfo(28)) * BasicInfo.PageSize
  MemoryUsage.NonPagedPoolSize = CCur(PerInfo(29)) * BasicInfo.PageSize
  If PerInfo(13) < QuotaLimits.PagefileLimit Then
    MemoryUsage.PagefileMemorySize = CCur(QuotaLimits.PagefileLimit) * BasicInfo.PageSize
  Else
    MemoryUsage.PagefileMemorySize = CCur(PerInfo(13)) * BasicInfo.PageSize
  End If
  MemoryUsage.VirtualMemorySize = BasicInfo.MaximumUserModeAddress - BasicInfo.MinimumUserModeAddress + 1
  MemoryUsage.AvailableVirtualMemory = MemoryUsage.VirtualMemorySize - Vm.VirtualSize
  SystemAPagefile = PerInfo(13) - PerInfo(12)
  ProcessAPagefile = QuotaLimits.PagefileLimit - Vm.PagefileUsage
  Status = Fix(MemoryUsage.AvailablePhysicalMemory / MemoryUsage.PhysicalMemorySize * 100)
  If SystemAPagefile > ProcessAPagefile Then
    MemoryUsage.AvailablePagefileMemory = CCur(SystemAPagefile) * BasicInfo.PageSize
  Else
    MemoryUsage.AvailablePagefileMemory = CCur(ProcessAPagefile) * BasicInfo.PageSize
  End If

End Function