StreamSocket.ConnectAsync Method

public:
 virtual IAsyncAction ^ ConnectAsync(EndpointPair ^ endpointPair) = ConnectAsync;

/// [Windows.Foundation.Metadata.Overload("ConnectWithEndpointPairAsync")]
IAsyncAction ConnectAsync(EndpointPair const& endpointPair);

[Windows.Foundation.Metadata.Overload("ConnectWithEndpointPairAsync")]
public IAsyncAction ConnectAsync(EndpointPair endpointPair);

function connectAsync(endpointPair)

Public Function ConnectAsync (endpointPair As EndpointPair) As IAsyncAction

Parameters

Returns

An asynchronous connect operation on a StreamSocket object.

Attributes

OverloadAttribute

Windows requirements

Remarks

If the EndpointPair object passed in the endpointPair parameter contains null for the LocalHostName property, then the system will supply the local IP address that will be used. If the EndpointPair object passed in the endpointPair parameter contains an empty string for the LocalServiceName property, then the system will supply the local TCP port that will be used.

In a UWP app, the StreamSocket class supports connecting to a remote endpoint when proxies are required to complete the connection. This support for proxies is automatic and transparent to the app. Connecting through proxies is not supported when a local host address is specified, so the LocalHostName property passed in the endpointPair parameter must be null. For more detailed information, see the remarks on Support for proxies in the StreamSocket class reference.

In a Windows Phone 8.x app, the StreamSocket class does not provide automatic support for proxies.

See also

• ConnectAsync(HostName, String)
• ConnectAsync(EndpointPair, SocketProtectionLevel)
• ConnectAsync(HostName, String, SocketProtectionLevel)
• ConnectAsync(HostName, String, SocketProtectionLevel, NetworkAdapter)
• EndpointPair
• How to set timeouts on socket operations
• How to set timeouts on socket operations

public:
 virtual IAsyncAction ^ ConnectAsync(EndpointPair ^ endpointPair, SocketProtectionLevel protectionLevel) = ConnectAsync;

/// [Windows.Foundation.Metadata.Overload("ConnectWithEndpointPairAndProtectionLevelAsync")]
IAsyncAction ConnectAsync(EndpointPair const& endpointPair, SocketProtectionLevel const& protectionLevel);

[Windows.Foundation.Metadata.Overload("ConnectWithEndpointPairAndProtectionLevelAsync")]
public IAsyncAction ConnectAsync(EndpointPair endpointPair, SocketProtectionLevel protectionLevel);

function connectAsync(endpointPair, protectionLevel)

Public Function ConnectAsync (endpointPair As EndpointPair, protectionLevel As SocketProtectionLevel) As IAsyncAction

Parameters

Returns

An asynchronous connect operation on a StreamSocket object.

Attributes

OverloadAttribute

Windows requirements

Remarks

If the EndpointPair object passed in the endpointPair parameter contains null for the LocalHostName property, then the system will supply the local IP address that will be used. If the EndpointPair object passed in the endpointPair parameter contains an empty string for the LocalServiceName property, then the system will supply the local TCP port that will be used.

If the EndpointPair object passed in the endpointPair parameter contains null for the LocalServiceName property, then an error will occur.

The [ConnectAsync(EndpointPair, SocketProtectionLevel) method is not exposed in JavaScript. This method can't be called from JavaScript since it has the same number of arguments as the ConnectAsync(HostName, String) method.

Apps written in JavaScript can't connect a StreamSocket using an EndpointPair using SSL directly. In order to connect an EndpointPair using SSL, JavaScript apps can use the following code instead.

var clientSocket = new Windows.Networking.Sockets.StreamSocket();
var remoteName = new Windows.Networking.HostName("www.contoso.com");
var myEndpointPair = EndpointPair();

// Set properties needed on the EndpointPair
// We only set remote properties and the localServiceName,
// But the localHostName could also be set

myEndpointPair.localServiceName = "12345";
myEndpointPair.remoteHostName = remoteName;
myEndpointPair.remoteServiceName = "http";

// First connect the socket without SSL
clientSocket.connectAsync(myEendpointPair>).then(function () {
    // Now upgrade the connection to SSL
    clientSocket.upgradeToSslAsync(SocketProtectionLevel.Ssl).then(function () {
        // now connected using SSL
    }
}   

When the protectionLevel parameter is set to a value that requires SSL or TLS, the socket connect operation may not timeout if the remote endpoint does not support SSL or TLS. This can occur if initial connect operation succeeds but the remote endpoint does not terminate the connection during the SSL handshake. To protect against this situation, an app should set a timeout on the connect operation when requesting SSL/TLS and abort the operation if the timeout expires. For more information on setting a timeout using JavaScript on socket operations, see How to set timeouts on socket operations . For more information on setting a timeout using VB, C#, or C++ on socket operations, see How to set timeouts on socket operations .

In a UWP app, the StreamSocket class supports connecting to a remote endpoint when proxies are required to complete the connection. This support for proxies is automatic and transparent to the app. Connecting through proxies is not supported when a local host address is specified, so the LocalHostName property passed in the endpointPair parameter must be null. For more detailed information, see the remarks on Support for proxies in the StreamSocket class reference.

In a Windows Phone 8.x app, the StreamSocket class does not provide automatic support for proxies.

See also

• ConnectAsync(EndpointPair)
• ConnectAsync(HostName, String)
• ConnectAsync(HostName, String, SocketProtectionLevel)
• ConnectAsync(HostName, String, SocketProtectionLevel, NetworkAdapter)
• EndpointPair
• SocketProtectionLevel
• How to set timeouts on socket operations
• How to set timeouts on socket operations

public:
 virtual IAsyncAction ^ ConnectAsync(HostName ^ remoteHostName, Platform::String ^ remoteServiceName) = ConnectAsync;

/// [Windows.Foundation.Metadata.DefaultOverload]
/// [Windows.Foundation.Metadata.Overload("ConnectAsync")]
/// [Windows.Foundation.Metadata.RemoteAsync]
IAsyncAction ConnectAsync(HostName const& remoteHostName, winrt::hstring const& remoteServiceName);

[Windows.Foundation.Metadata.DefaultOverload]
[Windows.Foundation.Metadata.Overload("ConnectAsync")]
[Windows.Foundation.Metadata.RemoteAsync]
public IAsyncAction ConnectAsync(HostName remoteHostName, string remoteServiceName);

function connectAsync(remoteHostName, remoteServiceName)

Public Function ConnectAsync (remoteHostName As HostName, remoteServiceName As String) As IAsyncAction

Parameters

Returns

An asynchronous connect operation on a StreamSocket object.

Attributes

DefaultOverloadAttribute OverloadAttribute RemoteAsyncAttribute

Windows requirements

Remarks

The remoteHostName and remoteServiceName parameters must be provided. If the remoteHostName is null or the remoteServiceName is null or an empty string, an error will occur.

In a UWP app, the StreamSocket class supports connecting to a remote endpoint when proxies are required to complete the connection. This support for proxies is automatic and transparent to the app. For more detailed information, see the remarks on Support for proxies in the StreamSocket class reference.

In a Windows Phone 8.x app, the StreamSocket class does not provide automatic support for proxies.

See also

• ConnectAsync(EndpointPair)
• ConnectAsync(EndpointPair, SocketProtectionLevel)
• ConnectAsync(HostName, String, SocketProtectionLevel)
• ConnectAsync(HostName, String, SocketProtectionLevel, NetworkAdapter)
• HostName
• How to set timeouts on socket operations
• How to set timeouts on socket operations

public:
 virtual IAsyncAction ^ ConnectAsync(HostName ^ remoteHostName, Platform::String ^ remoteServiceName, SocketProtectionLevel protectionLevel) = ConnectAsync;

/// [Windows.Foundation.Metadata.Overload("ConnectWithProtectionLevelAsync")]
/// [Windows.Foundation.Metadata.RemoteAsync]
IAsyncAction ConnectAsync(HostName const& remoteHostName, winrt::hstring const& remoteServiceName, SocketProtectionLevel const& protectionLevel);

[Windows.Foundation.Metadata.Overload("ConnectWithProtectionLevelAsync")]
[Windows.Foundation.Metadata.RemoteAsync]
public IAsyncAction ConnectAsync(HostName remoteHostName, string remoteServiceName, SocketProtectionLevel protectionLevel);

function connectAsync(remoteHostName, remoteServiceName, protectionLevel)

Public Function ConnectAsync (remoteHostName As HostName, remoteServiceName As String, protectionLevel As SocketProtectionLevel) As IAsyncAction

Parameters

Returns

An asynchronous connect operation on a StreamSocket object.

Attributes

OverloadAttribute RemoteAsyncAttribute

Windows requirements

Remarks

The remoteHostName and remoteServiceName parameters must be provided. If the remoteHostName is null or the remoteServiceName is null or an empty string, an error will occur.

When the protectionLevel parameter is set to a value that requires SSL or TLS, the socket connect operation may not timeout if the remote network destination does not support SSL or TLS. This can occur if initial connect operation succeeds but the remote host does not terminate the connection during the SSL handshake. To protect against this situation, an app should set a timeout on the connect operation when requesting SSL/TLS and abort the operation if the timeout expires. For more information on setting a timeout using JavaScript on socket operations, see How to set timeouts on socket operations . For more information on setting a timeout using VB, C#, or C++ on socket operations, see How to set timeouts on socket operations .

In a UWP app, the StreamSocket class supports connecting to a remote endpoint when proxies are required to complete the connection. This support for proxies is automatic and transparent to the app. For more detailed information, see the remarks on Support for proxies in the StreamSocket class reference.

In a Windows Phone 8.x app, the StreamSocket class does not provide automatic support for proxies.

See also

• ConnectAsync(EndpointPair)
• ConnectAsync(HostName, String)
• ConnectAsync(EndpointPair, SocketProtectionLevel)
• ConnectAsync(HostName, String, SocketProtectionLevel, NetworkAdapter)
• HostName
• SocketProtectionLevel
• How to set timeouts on socket operations
• How to set timeouts on socket operations

public:
 virtual IAsyncAction ^ ConnectAsync(HostName ^ remoteHostName, Platform::String ^ remoteServiceName, SocketProtectionLevel protectionLevel, NetworkAdapter ^ adapter) = ConnectAsync;

/// [Windows.Foundation.Metadata.Overload("ConnectWithProtectionLevelAndAdapterAsync")]
/// [Windows.Foundation.Metadata.RemoteAsync]
IAsyncAction ConnectAsync(HostName const& remoteHostName, winrt::hstring const& remoteServiceName, SocketProtectionLevel const& protectionLevel, NetworkAdapter const& adapter);

[Windows.Foundation.Metadata.Overload("ConnectWithProtectionLevelAndAdapterAsync")]
[Windows.Foundation.Metadata.RemoteAsync]
public IAsyncAction ConnectAsync(HostName remoteHostName, string remoteServiceName, SocketProtectionLevel protectionLevel, NetworkAdapter adapter);

function connectAsync(remoteHostName, remoteServiceName, protectionLevel, adapter)

Public Function ConnectAsync (remoteHostName As HostName, remoteServiceName As String, protectionLevel As SocketProtectionLevel, adapter As NetworkAdapter) As IAsyncAction

Parameters

Returns

An asynchronous connect operation on a StreamSocket object.

Attributes

OverloadAttribute RemoteAsyncAttribute

Remarks

The [ConnectAsync(Hostname, String, SocketProtectionLevel, NetworkAdapter) method binds to a network interface specified in the adapter parameter on the local computer and the remote hostname and service name specified in the remoteHostName and remoteServiceName parameters with the protection level specified in the protectionLevel parameter.

The remoteHostName and remoteServiceName parameters must be provided. If the remoteHostName is null or the remoteServiceName is null or an empty string, an error will occur. If the adapter parameter is null, an error will occur.

The name resolution mechanism used by the [ConnectAsync(Hostname, String, SocketProtectionLevel, NetworkAdapter) method is limited to the specified interface for the domain name system (DNS) namespace.

Using the specified network adapter is on a best-effort basis. Systems with adapters configured in weak-host or forwarding modes may use an adapter other than the specified adapter.

When the protectionLevel parameter is set to a value that requires SSL or TLS, the socket connect operation may not timeout if the remote network destination does not support SSL or TLS. This can occur if initial connect operation succeeds but the remote host does not terminate the connection during the SSL handshake. To protect against this situation, an app should set a timeout on the connect operation when requesting SSL/TLS and abort the operation if the timeout expires. For more information on setting a timeout using JavaScript on socket operations, see How to set timeouts on socket operations . For more information on setting a timeout using VB, C#, or C++ on socket operations, see How to set timeouts on socket operations .

An app can retrieve a valid NetworkAdapter by inspecting a HostName instance (using the NetworkInformation.GetHostNames method, for example) and retrieving the IPInformation object from the Hostname.IPInformation property. The IPInformation.NetworkAdapter property can be used to retrieve the associated NetworkAdapter.

In a UWP app, the StreamSocket class supports connecting to a remote endpoint when proxies are required to complete the connection. This support for proxies is automatic and transparent to the app. However, connecting through proxies is not supported when a specific network adapter is selected. So proxy support is disabled when the [ConnectAsync(HostName, String, SocketProtectionLevel, NetworkAdapter) method is used. For more detailed information, see the remarks on Support for proxies in the StreamSocket class reference.

In a Windows Phone 8.x app, the StreamSocket class does not provide automatic support for proxies.

See also

• ConnectAsync(EndpointPair)
• ConnectAsync(HostName, String)
• ConnectAsync(EndpointPair, SocketProtectionLevel)
• ConnectAsync(HostName, String, SocketProtectionLevel)
• IPInformation
• NetworkAdapter
• How to set timeouts on socket operations
• How to set timeouts on socket operations