QNetworkInformation 透過本機後端暴露各種網絡信息。 更多...
| 頭： |
#include <QNetworkInformation>
|
| CMake: |
find_package(Qt6 REQUIRED COMPONENTS Network)
target_link_libraries(mytarget PRIVATE Qt6::Network)
|
| qmake: |
QT += network
|
| Since: | Qt 6.1 |
| 繼承： | QObject |
| 枚舉類 | Feature { Reachability, CaptivePortal, TransportMedium, Metered } |
| flags | Features |
| 枚舉類 | Reachability { Unknown, Disconnected, Local, Site, Online } |
(從 6.3 起)
枚舉類
|
TransportMedium { Unknown, Ethernet, Cellular, WiFi, Bluetooth } |
(從 6.2 起)
isBehindCaptivePortal
: const bool
(從 6.3 起)
isMetered
: const bool
(從 6.3 起)
transportMedium
: const TransportMedium
| QString | backendName () const |
| bool | isBehindCaptivePortal () const |
| bool | isMetered () const |
| QNetworkInformation::Reachability | reachability () const |
(從 6.3 起)
QNetworkInformation::Features
|
supportedFeatures () const |
| bool | supports (QNetworkInformation::Features features ) const |
| QNetworkInformation::TransportMedium | transportMedium () const |
| void | isBehindCaptivePortalChanged (bool state ) |
| void | isMeteredChanged (bool isMetered ) |
| void | reachabilityChanged (QNetworkInformation::Reachability newReachability ) |
| void | transportMediumChanged (QNetworkInformation::TransportMedium current ) |
| QStringList | availableBackends () |
| QNetworkInformation * | instance () |
(從 6.4 起)
bool
|
loadBackendByFeatures (QNetworkInformation::Features features ) |
(從 6.4 起)
bool
|
loadBackendByName (QStringView backend ) |
(從 6.3 起)
bool
|
loadDefaultBackend () |
QNetworkInformation provides a cross-platform interface to network-related information through plugins.
Various plugins can have various functionality supported, and so you can load() plugins based on which features are needed.
QNetworkInformation is a singleton and stays alive from the first successful load() until destruction of the QCoreApplication object. If you destroy and re-create the QCoreApplication object you must call load() again.
注意： Because the class is a singleton while also relying on QCoreApplication , QNetworkInformation should always first be loaded in the same thread as the QCoreApplication object. This is because the object will also be destroyed in this thread, and various backend-specific components may rely on being destroyed in the same thread as it is created.
另請參閱 QNetworkInformation::Feature .
Lists all of the features that a plugin may currently support. This can be used in QNetworkInformation::load().
| 常量 | 值 | 描述 |
|---|---|---|
QNetworkInformation::Feature::Reachability
|
0x1
|
若插件支持此特徵，那麼
reachability
property will provide useful results. Otherwise it will always return
Reachability::Unknown
。另請參閱
QNetworkInformation::Reachability
.
|
QNetworkInformation::Feature::CaptivePortal
|
0x2
|
若插件支持此特徵，那麼
isBehindCaptivePortal
property will provide useful results. Otherwise it will always return
false
.
|
QNetworkInformation::Feature::TransportMedium
|
0x4
|
若插件支持此特徵，那麼
transportMedium
property will provide useful results. Otherwise it will always return
TransportMedium::Unknown
。另請參閱
QNetworkInformation::TransportMedium
.
|
QNetworkInformation::Feature::Metered
|
0x8
|
若插件支持此特徵，那麼
isMetered
property will provide useful results. Otherwise it will always return
false
.
|
Features 類型是 typedef 對於 QFlags <Feature>. It stores an OR combination of Feature values.
| 常量 | 值 | 描述 |
|---|---|---|
QNetworkInformation::Reachability::Unknown
|
0
|
If this value is returned then we may be connected but the OS has still not confirmed full connectivity, or this feature is not supported. |
QNetworkInformation::Reachability::Disconnected
|
1
|
Indicates that the system may have no connectivity at all. |
QNetworkInformation::Reachability::Local
|
2
|
Indicates that the system is connected to a network, but it might only be able to access devices on the local network. |
QNetworkInformation::Reachability::Site
|
3
|
Indicates that the system is connected to a network, but it might only be able to access devices on the local subnet or an intranet. |
QNetworkInformation::Reachability::Online
|
4
|
Indicates that the system is connected to a network and able to access the Internet. |
另請參閱 QNetworkInformation::reachability .
[since 6.3]
enum class QNetworkInformation::
TransportMedium
Lists the currently recognized media with which one can connect to the internet.
| 常量 | 值 | 描述 |
|---|---|---|
QNetworkInformation::TransportMedium::Unknown
|
0
|
Returned if either the OS reports no active medium, the active medium is not recognized by Qt, or the TransportMedium feature is not supported. |
QNetworkInformation::TransportMedium::Ethernet
|
1
|
Indicates that the currently active connection is using ethernet. Note: This value may also be returned when Windows is connected to a Bluetooth personal area network. |
QNetworkInformation::TransportMedium::Cellular
|
2
|
Indicates that the currently active connection is using a cellular network. |
QNetworkInformation::TransportMedium::WiFi
|
3
|
Indicates that the currently active connection is using Wi-Fi. |
QNetworkInformation::TransportMedium::Bluetooth
|
4
|
Indicates that the currently active connection is connected using Bluetooth. |
該枚舉在 Qt 6.3 引入。
另請參閱 QNetworkInformation::transportMedium .
[read-only, since 6.2]
isBehindCaptivePortal
: const
bool
Lets you know if the user's device is behind a captive portal.
This property indicates if the user's device is currently known to be behind a captive portal. This functionality relies on the operating system's detection of captive portals and is not supported on systems that don't report this. On systems where this is not supported this will always return
false
.
該特性在 Qt 6.2 引入。
訪問函數：
| bool | isBehindCaptivePortal () const |
通知程序信號：
| void | isBehindCaptivePortalChanged (bool state ) |
[read-only, since 6.3]
isMetered
: const
bool
校驗當前連接是否有計量
This property returns whether the current connection is (known to be) metered or not. You can use this as a guiding factor to decide whether your application should perform certain network requests or uploads. For instance, you may not want to upload logs or diagnostics while this property is
true
.
該特性在 Qt 6.3 引入。
訪問函數：
| bool | isMetered () const |
通知程序信號：
| void | isMeteredChanged (bool isMetered ) |
[read-only]
reachability
: const
Reachability
This property holds the current state of the system's network connectivity.
Indicates the level of connectivity that can be expected. Do note that this is only based on what the plugin/operating system reports. In certain scenarios this is known to be wrong. For example, on Windows the 'Online' check, by default, is performed by Windows connecting to a Microsoft-owned server. If this server is for any reason blocked then it will assume it does not have Online reachability. Because of this you should not use this as a pre-check before attempting to make a connection.
訪問函數：
| QNetworkInformation::Reachability | reachability () const |
通知程序信號：
| void | reachabilityChanged (QNetworkInformation::Reachability newReachability ) |
[read-only, since 6.3]
transportMedium
: const
TransportMedium
This property holds the currently active transport medium for the application
This property returns the currently active transport medium for the application, on operating systems where such information is available.
When the current transport medium changes a signal is emitted, this can, for instance, occur when a user leaves the range of a WiFi network, unplugs their ethernet cable or enables Airplane mode.
該特性在 Qt 6.3 引入。
訪問函數：
| QNetworkInformation::TransportMedium | transportMedium () const |
通知程序信號：
| void | transportMediumChanged (QNetworkInformation::TransportMedium current ) |
[static]
QStringList
QNetworkInformation::
availableBackends
()
Returns a list of the names of all currently available backends.
返迴當前加載的後端名稱。
[static]
QNetworkInformation
*QNetworkInformation::
instance
()
Returns a pointer to the instance of the QNetworkInformation ，若有的話。
另請參閱 load ().
[static, since 6.4]
bool
QNetworkInformation::
loadBackendByFeatures
(
QNetworkInformation::Features
features
)
Load a backend which supports features .
返迴
true
if it managed to load the requested backend or if it was already loaded. Returns
false
否則。
該函數在 Qt 6.4 引入。
另請參閱 instance .
[static, since 6.4]
bool
QNetworkInformation::
loadBackendByName
(
QStringView
backend
)
Attempts to load a backend whose name matches backend (case insensitively).
返迴
true
if it managed to load the requested backend or if it was already loaded. Returns
false
否則。
該函數在 Qt 6.4 引入。
另請參閱 instance .
[static, since 6.3]
bool
QNetworkInformation::
loadDefaultBackend
()
試圖加載平颱默認後端。
注意： Starting with 6.7 this tries to load any backend that supports Reachability if the platform-default backend is not available or fails to load. If this also fails it will fall back to a backend that only returns the default values for all properties.
This platform-to-plugin mapping is as follows:
| 平颱 | 插件名 |
|---|---|
| Windows | networklistmanager |
| Apple (macOS/iOS) | scnetworkreachability |
| Android | android |
| Linux | networkmanager |
This function is provided for convenience where the logic earlier is good enough. If you require a specific plugin then you should call loadBackendByName () 或 loadBackendByFeatures () directly instead.
Determines a suitable backend to load and returns
true
if this backend is already loaded or on successful loading of it. Returns
false
if any other backend has already been loaded, or if loading of the selected backend fails.
該函數在 Qt 6.3 引入。
[since 6.3]
QNetworkInformation::Features
QNetworkInformation::
supportedFeatures
() const
返迴當前後端支持的所有特徵。
該函數在 Qt 6.3 引入。
返迴
true
若目前加載的後端支持
features
.