Provider Classes

In EasyLanguage, provider classes represent a group of component classes whose names end with the word 'Provider' and are used to access data from one or more classes referenced in the provider, including changes to the data in real-time. The provider classes inherit characteristics from the tsdata.common.DataProvider class that allows you to connect an event handler method in your EasyLanguage code to a provider Updated event or StateChanged event. An Updated event fires when the provider is loaded for the first time and, thereafter, when the data contained in the provider is updated real-time. The StatusChanged event reports a change in the loaded or unloaded state of the provider. Providers also inherit from the elsystem.ElComponent class that allows you to drag and drop a provider component from the toolbox into your EasyLanguage document and to edit the values for the component using the Properties editor.

Providers

Name	Description
AccountsProvider	Gets account balance and other information from specified TradeStation accounts.
FundamentalQuotesProvider	Gets information from specified fundamental fields for a symbol.
MarketDepthProvider	Gets market depth bid and ask levels regarding specified ECN books for a symbol.
NewsProvider	Gets news items for specified symbols and date ranges.
OrdersProvider	Gets updated order status information based on user specified filters.
PositionsProvider	Gets information about positions from specified TradeStation accounts.
PriceSeriesProvider	Gets a historical price series for a specified symbol and interval, including real-time updates.
QuotesProvider	Gets information from specified quote fields for a symbol.
RSSProvider	Gets RSS news items from a specified RSS feed and web address.
SymbolAttributesProvider	Gets information and attributes for a specified symbol.

Updated Event

An Updated event for providers calls a user created method using a similar format.

<provider>_Updated(Object Sender, <prefix>UpdatedEventArgs Args)

The name of the method is typically made up of the <provider> component name followed by _Updated which is, by default, the name of the component and an instance number such as AccountsProvider1.

The handler will usually be called in two cases. The first case is when the provider is loaded for the first time and the second case is when a change occurs to the data contained in the provider, such as a real-time update to a value.

The Sender parameter identifies the object that fires the event

The Args parameter contains information about the nature of the change that happened to the provider and some kind of contextal information as to what specific object within the provider was affected by this change.

For example, when an Order referenced by an OrdersProvider is filled, the Sender tells you what Order object the event belongs to and the Args object tells you what order was filled.

However when the Updated event is called because the provider was loaded initially this “contextual” information is not available.

The way a user can tell if the reason for the call is because of the initial load or because a realtime event is by using the property Reason of the args object.

StatusChanged Event

A StatusChanged event for providers calls a user created method using a similar format.