内容

• 公共类型
• 公共变量
• 相关非成员
• 详细描述

Filter Struct

struct QCanBusDevice ::Filter

QCanBusDevice::Filter struct defines a filter for CAN bus frames. 更多...

该结构在 Qt 5.8 引入。

• 所有成员列表，包括继承成员

公共类型

enum	FormatFilter { MatchBaseFormat, MatchExtendedFormat, MatchBaseAndExtendedFormat }
flags	FormatFilters

公共变量

QCanBusDevice::Filter::FormatFilter	format
QCanBusFrame::FrameId	frameId
QCanBusFrame::FrameId	frameIdMask
QCanBusFrame::FrameType	type

相关非成员

bool	operator!= (const Filter & a , const Filter & b )
bool	operator== (const Filter & a , const Filter & b )

详细描述

A list of QCanBusDevice::Filter instances is passed to QCanBusDevice::setConfigurationParameter () to enable filtering. If a received CAN frame matches at least one of the filters in the list, the QCanBusDevice will accept it.

The example below demonstrates how to use the struct:

QCanBusDevice::Filter filter;
QList<QCanBusDevice::Filter> filterList;
// filter all CAN bus packages with id 0x444 (base) or 0xXXXXX444 (extended)
filter.frameId = 0x444u;
filter.frameIdMask = 0x7FFu;
filter.format = QCanBusDevice::Filter::MatchBaseAndExtendedFormat;
filter.type = QCanBusFrame::InvalidFrame;
filterList.append(filter);
// filter all DataFrames with extended CAN bus package format
filter.frameId = 0x0;
filter.frameIdMask = 0x0;
filter.format = QCanBusDevice::Filter::MatchExtendedFormat;
filter.type = QCanBusFrame::DataFrame;
filterList.append(filter);
// apply filter
device->setConfigurationParameter(QCanBusDevice::RawFilterKey, QVariant::fromValue(filterList));
					

成员类型文档编制

enum Filter:: FormatFilter
flags Filter:: FormatFilters

This enum describes the format pattern, which is used to filter incoming CAN bus frames.

常量	值	描述
QCanBusDevice::Filter::MatchBaseFormat	0x0001	The CAN bus frame must use the base frame format (11 bit identifier).
QCanBusDevice::Filter::MatchExtendedFormat	0x0002	The CAN bus frame must use the extended frame format (29 bit identifier).
QCanBusDevice::Filter::MatchBaseAndExtendedFormat	0x0003	The CAN bus frame can have a base or an extended frame format.

The FormatFilters type is a typedef for QFlags <FormatFilter>. It stores an OR combination of FormatFilter values.

成员变量文档编制

QCanBusDevice::Filter::FormatFilter Filter:: format

This variable holds the frame format of the matching CAN bus frame.

By default this field is set to QCanBusDevice::Filter::MatchBaseAndExtendedFormat .

QCanBusFrame::FrameId Filter:: frameId

This variable holds the frame id used to filter the incoming frames.

The frameId is used in conjunction with frameIdMask . The matching is successful if the following evaluates to true :

(receivedFrameId & frameIdMask) == (frameId & frameIdMask)
					

By default this field is set to 0x0 .

另请参阅 frameIdMask .

QCanBusFrame::FrameId Filter:: frameIdMask

This variable holds the bit mask that is applied to the frame id of the filter and the received frame.

The two frame ids are matching if the following evaluates to true :

(receivedFrameId & frameIdMask) == (frameId & frameIdMask)
					

By default this field is set to 0x0 .

另请参阅 frameId .

QCanBusFrame::FrameType Filter:: type

This variable holds the type of the frame to be filtered.

Any CAN bus frame type can be matched by setting this variable to QCanBusFrame::InvalidFrame . The filter object is invalid if type is equal to QCanBusFrame::UnknownFrame .

By default this field is set to QCanBusFrame::InvalidFrame .

另请参阅 QCanBusFrame::FrameType .

相关非成员

bool operator!= (const Filter & a , const Filter & b )

返回 true , if the filter a is not equal to the filter b ，否则返回 false .

bool operator== (const Filter & a , const Filter & b )

返回 true , if the filter a is equal to the filter b ，否则返回 false .