What is activity and activity classification?

What is activity:
There are about 28 types of activities currently provided, which are divided into 8 categories. activity is a compiled module of workflow and an executable, reusable, and composite unit. A basic activity is a step of workflow. A complex activity can contain other activities. an activity can be a custom activity provided by a partner or customer. This activity may complete some specific business logic. you can define attributes and events in an activity. The methods used by workflow in the activity are implemented by the author of the activity (for example, execute), and are called by Workflow or the designer, it can be compiled in workflow or used as a reusable library dependent on workflow. it can be said that the most important thing about an activity is reuse. reuse is not only code reuse, but business logic reuse. This is also the flexibility of workflow applications.

Activity category:
There are about 28 types of activities currently provided, which are divided into eight categories:
1: control flow activity: Control Flow
2: workflow lifetime activity: Workflow-related
3: Event waiting activity: event class
4: transaction and exception activity: transaction and exception handling class
5: Data-centic activity: Data (Exchange) processing class
6: WebService activity: Processing weserivice
7: The Code activity: code processing class
8: State workflow activity: state machine workflow processing class
9: others, custom activity: User-defined class

The specific activity in the category is as follows:
1. Control Flow activity: Control Flow
Sequence activity: sequential flow
Parallel activity: Parallel Flow
Ifelse activity: Conditional judgment process
While activity: cyclic process
Conditionedactivitygroup: Condition Group
Replicator activity: self-replication, which can replicate instances at runtime
Delay activity: delayed execution

2. workflow lifetime activity: Workflow-related
Invokeworkflow activity: Call and execute another Workflow
Suspend activity: Pause the currently executed Workflow
Terminate activity: abort a Workflow

3. Event waiting activity: event class
Eventdriven activity: Wait for the event driver. Specify the names and parameters of the events to be processed.
Listen activity: listens for messages. This can listen on many messages at the same time. A listin contains multiple eventdriven

4. Transaction and exception activity: transaction and exception handling class
Transaction context activity: processes the context of a transaction and supports short-term and long-term transactions.
Throw activity: throw an exception
Exceptionhandler: Exception Handling
Compensate activity: compensation processing, which can only be placed in exception, processing some rollback processing, etc.

5. Data-centic activity: Data (Exchange) processing class: used for data exchange between WF processing space and host Space
Updatedata activity: WF updates data to the host
Selectdata activity: WF sends a request to the host
Waitfordata activity:
Waitforquery activity: the host is sent to WF, and WF returns datasource.

6. WebService activity: processing of weserivice
Invokewebservice activity: Call WebService
Webservicereceive Activity
Webserviceresponse Activity

7. The Code activity: code processing class
Code activity: You can write some code, but I don't think this is a good solution, because this logic is a bit written into the program.

8. State workflow activity: state machine workflow processing class
State: status. A state machine. A workflow must have an initial state and an end state.
Stateinitialization: initial state. I have never used this.
Setstate: sets the next state.
9. Custom activity: Custom status.