QNetworkDatagram ¶

函数 ¶

特征支持 ¶

Some features of QNetworkDatagram are not supported in all operating systems. Only the address and ports of the remote host (sender in received packets and destination for outgoing packets) are supported in all systems. On most operating systems, the other features are supported only for IPv6. Software should check at runtime whether the rest could be determined for IPv4 addresses.

当前特征支持如下所示：

操作系统	本地地址	跳跃计数	接口索引
FreeBSD	支持	支持	仅 IPv6
Linux	支持	支持	支持
OS X	支持	支持	仅 IPv6
其它 Unix 支持 RFC 3542	仅 IPv6	仅 IPv6	仅 IPv6
Windows (桌面)	支持	支持	支持
Windows RT	不支持	不支持	不支持

另请参阅

QUdpSocket QNetworkInterface

class QNetworkDatagram ¶

QNetworkDatagram(data[, destinationAddress=QHostAddress()[, port=0]])

QNetworkDatagram(other)

param port

quint16

param other

QNetworkDatagram

param destinationAddress

QHostAddress

param data

QByteArray

创建 QNetworkDatagram object with no payload data and undefined destination address.

The payload can be modified by using setData() and the destination address can be set with setDestination() .

If the destination address is left undefined, writeDatagram() will attempt to send the datagram to the address last associated with, by using connectToHost() .

创建 QNetworkDatagram object and sets data as the payload data, along with destinationAddress and port as the destination address of the datagram.

PySide2.QtNetwork.QNetworkDatagram. clear ( ) ¶

清零负载数据和元数据在此 QNetworkDatagram 对象，将它们重置到其默认值。

PySide2.QtNetwork.QNetworkDatagram. data ( ) ¶

返回类型

QByteArray

Returns the data payload of this datagram. For a datagram received from the network, it contains the payload of the datagram. For an outgoing datagram, it is the datagram to be sent.

Note that datagrams can be transmitted with no data, so the returned QByteArray 可能为空。

另请参阅

setData()

PySide2.QtNetwork.QNetworkDatagram. destinationAddress ( ) ¶

返回类型

QHostAddress

Returns the destination address associated with this datagram. For a datagram received from the network, it is the address the peer node sent the datagram to, which can either be a local address of this machine or a multicast or broadcast address. For an outgoing datagrams, it is the address the datagram should be sent to.

If no destination address was set on this datagram, the returned object will report true to isNull() .

另请参阅

senderAddress() destinationPort() setDestination()

PySide2.QtNetwork.QNetworkDatagram. destinationPort ( ) ¶

返回类型

int

Returns the port number of the destination associated with this datagram. For a datagram received from the network, it is the local port number that the peer node sent the datagram to. For an outgoing datagram, it is the peer port the datagram should be sent to.

If no destination address was associated with this datagram, this function returns -1.

另请参阅

destinationAddress() senderPort() setDestination()

PySide2.QtNetwork.QNetworkDatagram. hopLimit ( ) ¶

返回类型

int

Returns the hop count limit associated with this datagram. The hop count limit is the number of nodes that are allowed to forward the IP packet before it expires and an error is sent back to the sender of the datagram. In IPv4, this value is usually known as “time to live” (TTL).

If this datagram was received from the network, this is the remaining hop count of the datagram after reception and was decremented by 1 by each node that forwarded the packet. A value of -1 indicates that the hop limit count not be obtained.

If this is an outgoing datagram, this is the value to be set in the IP header upon sending. A value of -1 indicates the operating system should choose the value.

另请参阅

setHopLimit()

PySide2.QtNetwork.QNetworkDatagram. interfaceIndex ( ) ¶

返回类型

uint

Returns the interface index this datagram is associated with. The interface index is a positive number that uniquely identifies the network interface in the operating system. This number matches the value returned by index() for the interface.

If this datagram was received from the network, this is the index of the interface that the packet was received from. If this is an outgoing datagram, this is the index of the interface that the datagram should be sent on.

A value of 0 indicates that the interface index is unknown.

另请参阅

setInterfaceIndex()

PySide2.QtNetwork.QNetworkDatagram. isNull ( ) ¶

返回类型

bool

返回 true，若此 QNetworkDatagram object is null. This function is the opposite of isValid() .

PySide2.QtNetwork.QNetworkDatagram. isValid ( ) ¶

返回类型

bool

返回 true，若此 QNetworkDatagram object is valid. A valid QNetworkDatagram object contains at least one sender or receiver address. Valid datagrams can contain empty payloads.

PySide2.QtNetwork.QNetworkDatagram. makeReply ( payload ) ¶

参数

payload – QByteArray

返回类型

QNetworkDatagram

PySide2.QtNetwork.QNetworkDatagram. senderAddress ( ) ¶

返回类型

QHostAddress

Returns the sender address associated with this datagram. For a datagram received from the network, it is the address of the peer node that sent the datagram. For an outgoing datagrams, it is the local address to be used when sending.

If no sender address was set on this datagram, the returned object will report true to isNull() .

另请参阅

destinationAddress() senderPort() setSender()

PySide2.QtNetwork.QNetworkDatagram. senderPort ( ) ¶

返回类型

int

Returns the port number of the sender associated with this datagram. For a datagram received from the network, it is the port number that the peer node sent the datagram from. For an outgoing datagram, it is the local port the datagram should be sent from.

If no sender address was associated with this datagram, this function returns -1.

另请参阅

senderAddress() destinationPort() setSender()

PySide2.QtNetwork.QNetworkDatagram. setData ( data ) ¶

参数

data – QByteArray

Sets the data payload of this datagram to data . It is usually not necessary to call this function on received datagrams. For outgoing datagrams, this function sets the data to be sent on the network.

Since datagrams can empty, an empty QByteArray is a valid value for data .

另请参阅

data()

PySide2.QtNetwork.QNetworkDatagram. setDestination ( address , port ) ¶

参数

• address – QHostAddress

• port – quint16

Sets the destination address associated with this datagram to be the address address and port number port . The destination address and port numbers are usually set by QUdpSocket upon reception, so there’s no need to call this function on a received datagram.

For outgoing datagrams, this function can be used to set the address the datagram should be sent to. It can be the unicast address used to communicate with the peer or a broadcast or multicast address to send to a group of devices.

另请参阅

writeDatagram() destinationAddress() destinationPort() setSender()

PySide2.QtNetwork.QNetworkDatagram. setHopLimit ( count ) ¶

参数

count – int

Sets the hop count limit associated with this datagram to count . The hop count limit is the number of nodes that are allowed to forward the IP packet before it expires and an error is sent back to the sender of the datagram. In IPv4, this value is usually known as “time to live” (TTL).

It is usually not necessary to call this function on datagrams received from the network.

If this is an outgoing packet, this is the value to be set in the IP header upon sending. The valid range for the value is 1 to 255. This function also accepts a value of -1 to indicate that the operating system should choose the value.

另请参阅

hopLimit()

PySide2.QtNetwork.QNetworkDatagram. setInterfaceIndex ( index ) ¶

参数

index – uint

Sets the interface index this datagram is associated with to index . The interface index is a positive number that uniquely identifies the network interface in the operating system. This number matches the value returned by index() for the interface.

It is usually not necessary to call this function on datagrams received from the network.

If this is an outgoing packet, this is the index of the interface the datagram should be sent on. A value of 0 indicates that the operating system should choose the interface based on other factors.

Note that the interface index can also be set with setScopeId() for IPv6 destination addresses and then with setDestination() . If the scope ID set in the destination address and index are different and neither is zero, it is undefined which interface the operating system will send the datagram on.

另请参阅

interfaceIndex() setInterfaceIndex()

PySide2.QtNetwork.QNetworkDatagram. setSender ( address [ , port=0 ] ) ¶

参数

• address – QHostAddress

• port – quint16

Sets the sender address associated with this datagram to be the address address and port number port . The sender address and port numbers are usually set by QUdpSocket upon reception, so there’s no need to call this function on a received datagram.

For outgoing datagrams, this function can be used to set the address the datagram should carry. The address address must usually be one of the local addresses assigned to this machine, which can be obtained using QNetworkInterface . If left unset, the operating system will choose the most appropriate address to use given the destination in question.

The port number port must be the port number associated with the socket, if there is one. The value of 0 can be used to indicate that the operating system should choose the port number.

另请参阅

writeDatagram() senderAddress() senderPort() setDestination()

PySide2.QtNetwork.QNetworkDatagram. swap ( other ) ¶

参数

other – QNetworkDatagram

交换此实例采用 other .