Lightstreamer - Quickstart Example - .NET Client

The Quickstart Example provides the source code to build a very simple and basic client application, used to test the capability of the Client APIs to connect and receive data from Lightstreamer Server. The example can be used to familiarize with the Client APIs and as a reference on how to use them, and can be used as a starting point for client application implementations.

This project contains the C# source files of a sample application, which shows how the Lightstreamer .NET Standard Client API can be used to connect to Lightstreamer Server. The Client API version in use in this example support the Unified Client API model.

Details

The example basically connects to the server and performs a subscription, printing on the console the incoming Item Updates. Some connection parameters and the type of subscription performed depend on the parameters passed in the command line; which in the right order are:

• HOST: the complete hostname of the Lightstreamer server to target. For example to hit our Demos server use https://push.lightstreamer.com
• MODE: should be
  • 0 for Stock-List subscription targeting the QUOTE_ADAPTER Data Adapter
  • 1 for Chat subscription targeting the CHAT_ROOM Data Adapter
  • 2 for Portfolio subscription targeting the PORTFOLIO_ADAPTER Data Adapter
• [MAX_FREQUENCY]: double value in oreder to request to the Lightstreamer server a max frequency, 0.0 means unlimited (optional)
• [FORCE_TRANSPORT]: could be WS-STREAMING, HTTP-STREAMING, WS-POLLING, or HTTP-POLLING. If no value passed or 'no' string passed the STREAM-SENSE algorithm of the Lightstreamer client lib will set-up the connection with the best transport available (optional)
• [PROXY_ON]: 0/1 flag to use or not to use an http proxy (optional)
• [PROXY_ADDRESS]: in the case, the ip address of the http proxy (optional)
• [PROXY_PORT]: in the case, the port to connect the http proxy (optional)

One more functionality shown is the submission of a message representing an order for the Portfolio Demo. To run this case, the parameters to be passed in the command line are:

• HOST: the complete hostname of the Lightstreamer server to target. For example to hit our Demos server use https://push.lightstreamer.com
• MODE: should be
  • 3 for Order submission message targeting the PORTFOLIO_ADAPTER Data Adapter
• [ITEM]: name of an item supported by the Portfolio Demo
• [QUANTITY]: number of stocks to buy or (if negative) to sell
• [PROXY_ON]: 0/1 flag to use or not to use an http proxy (optional)
• [PROXY_ADDRESS]: in the case, the ip address of the http proxy (optional)
• [PROXY_PORT]: in the case, the port to connect the http proxy (optional)

Dig the Code

The application is divided into 6 main classes.

• QuickStart.cs: this is the main class, implementing the connection to the Lightstreamer server, the subscription of Items and, in case of Chat and Order mode, the send of text messages.
• OrderMessageListener.cs: is a very basic implementation of the ClientMessageListener interface. Basically just print on the console every feedback received from the order message submission.
• SystemOutClientListener.cs: is a very basic custom implementation of the ClientListener interface. An instance of this class, listening to a LightstreamerClient instance (through the addListener method) will print on the standard output information about the status of the connection and will trigger the subscription request upon the status change event indicating the client session is alive.
• QuoteListener.cs, PortfolioListener.cs, and ChatSubscriptionListener.cs: are very basic custom implementations of the SubscriptionListener interface. Basically just print on the console every event received.

Install

If you want to install a version of this demo pointing to our Demo Server, follow these steps:

• Since the app is an example of Framework-Dependent Deployment (FDD) relies on the presence of a shared system-wide version of .NET Core on the target system.
• Download the deploy.zip file that you can find in the deploy release of this project and extract the deploy_local folder.
• Execute the LaunchMe.bat; you can modify it and change the parameters to run the various demo versions.

Build

To build a version of this example, pointing to your local Lightstreamer Server instance, follow the steps below.

• you'll need to install the following adapters (depending on which quickstart example you want to run you might not need them all):
  • The CHAT_ROOM (see the Lightstreamer - Basic Chat Demo - Java Adapter).
  • The QUOTE_ADAPTER (see the Lightstreamer - Stock-List Demo - Java Adapter)
  • The PORTFOLIO_ADAPTER ( see the Lightstreamer - Portfolio Demo - Java Adapter), Follow the instructions on those projects to get them up and running (in the portfolio case, you'll need the full version). [If you want to skip the Adapters installation you could target our Demos server (see below)]
• Launch the Lightstreamer Server.
• Create a new C# project: from the "New Project..." wizard, choose the ".NET Core" and then "App Console" template.
• From the "Solution Explorer", delete the default Program.cs.
• Add all the files provided in the src folder of this project; from the "Add -> Existing Item" dialog.
• You should complete this project with the Lightstreamer .NET Standard Client library, to be used for the build process, trough NuGet. Follow these steps:
  • In the "Solution Explorer" tab, right click on the project and choose Manage NuGet Packages ...
  • In the Search text box enter Lightstreamer
  • Choose the Lightstreamer.DotNetStandard.Client last version then click Install and then Ok
  • Check out that among the References of your project Lightstreamer.DotNetStandard.Client was added.
• Build solution.
• In the "Launch profiles" add as "Command Line Arguments" suitable values for the quickstart example you want to run (see above). The HOST argument should be http://localhost; however, if you skipped the Adapter installation, you could address our Demo Server: https://push.lightstreamer.com
• Run the demo.

See Also

Lightstreamer Adapters Needed by These Clients

• Lightstreamer - Stock-List Demo - Java Adapter
• Lightstreamer - Portfolio Demo - Java Adapter
• Lightstreamer - Basic Chat Demo - Java Adapter)
• Lightstreamer - Reusable Metadata Adapters - Java Adapter

Related Projects

• Lightstreamer .NET Standard Client SDK
• Lightstreamer - Basic Stock-List Demo - .NET Client

Lightstreamer Compatibility Notes

• Compatible with Lightstreamer .NET Standard Client Library version 6 or newer.
• For a version of this demo compatible with Lightstreamer .NET Standard Client Library version 5.x, please refer to this tag.
• For a version of this demo compatible with .NET Standard Client library version 4.x, please refer to this tag.
• Ensure that .NET Standard Client API is supported by Lightstreamer Server license configuration.