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OnQueryQuotasControlInformation event/delegate/callback


Pascal    C++ (Lib)    C++ (VCL)    C++ (.NET)    C#    VB.NET    Java 

CallbackFileSystem     See also    


The event is fired when the OS needs to get default quota information for the volume.


    property OnQueryQuotasControlInformation : TCbFQueryQuotasControlInformationEvent;
    TCbFQueryQuotasControlInformationEvent = procedure( Sender : TObject; var DefaultQuotaThreshold : Int64; var DefaultQuotaLimit: Int64; var FileSystemControlFlags : LongWord; ) of object;

[C++ (Lib)]
    void (__stdcall *CbFQueryQuotasControlInformationEvent)( void* Sender, long long * DefaultQuotaThreshold, long long * DefaultQuotaLimit, unsigned long *FileSystemControlFlags );

[C++ (VCL)]
    typedef void (__closure *TCbFQueryQuotasControlInformationEvent)( System::TObject* Sender, __int64 &DefaultQuotaThreshold, __int64 &DefaultQuotaLimit, unsigned long &FileSystemControlFlags );

[C++ (.NET)]
    public __delegate void CbFQueryQuotasControlInformationEvent( CallbackFileSystem^ Sender, Int64% DefaultQuotaThreshold, Int64% DefaultQuotaLimit, UInt32% FileSystemControlFlags );

    public void CbFQueryQuotasControlInformationEvent( CallbackFileSystem Sender, ref Int64 DefaultQuotaThreshold, ref Int64 DefaultQuotaLimit, ref UInt32 FileSystemControlFlags );

    Sub CbFQueryQuotasControlInformationEvent( ByVal Sender As CallbackFileSystem, ByRef DefaultQuotaThreshold As Int64, ByRef DefaultQuotaLimit As Int64, ByRef FileSystemControlFlags As UInt32 )

    void ICbFsDiskQuotaEvents.onQueryQuotasControlInformation( CallbackFileSystem sender, );


  • Sender - reference to the class that called the delegate/event handler
  • DefaultQuotaThreshold - default value in bytes, after which the user is warned about approaching the limit
  • DefaultQuotaLimit - default limit of the user quota on the volume
  • FileSystemControlFlags - flags that describe the state of the disk quota information


This event is fired when the OS needs to set default quota parameters for the volume.

The parameters are described in MSDN article (https://msdn.microsoft.com/en-us/data/ff540258%28v=vs.100%29).

The callback / event is optional, i.e. you don't have to handle it if you don't support disk quotas.

Error handling

See Error handling topic for detailed information about how to report errors, which occur in the event handlers, back to Callback File System.

See also

OnQueryQuotas event     OnSetQuotas event     OnSetQuotasControlInformation event    

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