DnsEndPoint Constructor (String, Int32, AddressFamily)


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Initializes a new instance of the DnsEndPoint class with the host name or string representation of an IP address, a port number, and an address family.

Namespace:   System.Net
Assembly:  System (in System.dll)

Public Sub New (
	host As String,
	port As Integer,
	addressFamily As AddressFamily


Type: System.String

The host name or a string representation of the IP address.

Type: System.Int32

The port number associated with the address, or 0 to specify any available port. port is in host order.

Type: System.Net.Sockets.AddressFamily

One of the AddressFamily values.

Exception Condition

The host parameter contains an empty string.


addressFamily is Unknown.


The host parameter is a null.


port is less than MinPort.


port is greater than MaxPort.

The DnsEndPoint(String, Int32, AddressFamily) constructor can be used to initialize a DnsEndPoint class using either a host name or a string that represents an IP address, a port, and an address family.

When using the constructor with a host name rather than a string representation of an IP address, the address family restricts DNS resolution to prefer addresses of the specified address family value. When using the constructor with the address family specified as Unknown, the address family of the DnsEndPoint will remain Unknown even after use. The AddressFamily property of any Socket that is created by calls to the ConnectAsync method will be the address family of the first address to which a connection can be successfully established (not necessarily the first address to be resolved).

Universal Windows Platform
Available since 10
.NET Framework
Available since 4.0
Available since 2.0
Windows Phone Silverlight
Available since 7.1
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