# Class FormBase

OptimaJet.Workflow.Core.FormBase

Defines the low-level metadata and execution contract for forms exposed to the workflow designer.

Namespace: [OptimaJet.Workflow.Core](https://api.workflowengine.io/core/OptimaJet.Workflow.Core/)

```csharp
public abstract class FormBase
```

## Type Hierarchy

-   FormBase Current type
    -   [ActivityBase](https://api.workflowengine.io/core/OptimaJet.Workflow.Core/ActivityBase/)
        -   [ActivityBaseFromAction](https://api.workflowengine.io/core/OptimaJet.Workflow.Plugins.Activity/ActivityBaseFromAction/)
        -   [ActivityBaseFromActionAsync](https://api.workflowengine.io/core/OptimaJet.Workflow.Plugins.Activity/ActivityBaseFromActionAsync/)
        -   [BpmnActivityBase](https://api.workflowengine.io/bpmn-plugin/OptimaJet.Workflow.BpmnPlugin.Elements/BpmnActivityBase/)
            -   [EndEvent](https://api.workflowengine.io/bpmn-plugin/OptimaJet.Workflow.BpmnPlugin.Elements/EndEvent/)
            -   [ExclusiveGateway](https://api.workflowengine.io/bpmn-plugin/OptimaJet.Workflow.BpmnPlugin.Elements/ExclusiveGateway/)
            -   [MessageCatchEvent](https://api.workflowengine.io/bpmn-plugin/OptimaJet.Workflow.BpmnPlugin.Elements/MessageCatchEvent/)
            -   [ParallelGateway](https://api.workflowengine.io/bpmn-plugin/OptimaJet.Workflow.BpmnPlugin.Elements/ParallelGateway/)
            -   [ServiceTaskActivity](https://api.workflowengine.io/bpmn-plugin/OptimaJet.Workflow.BpmnPlugin.Elements/ServiceTaskActivity/)
            -   [StartEvent](https://api.workflowengine.io/bpmn-plugin/OptimaJet.Workflow.BpmnPlugin.Elements/StartEvent/)
            -   [TerminateEvent](https://api.workflowengine.io/bpmn-plugin/OptimaJet.Workflow.BpmnPlugin.Elements/TerminateEvent/)
            -   [TimerCatchEvent](https://api.workflowengine.io/bpmn-plugin/OptimaJet.Workflow.BpmnPlugin.Elements/TimerCatchEvent/)
        -   [Decision](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Plugins.BasicsPlugin/Decision/)
        -   [DecisionTable](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Plugins.BasicsPlugin/DecisionTable/)
        -   [GeneratedCustomActivity](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Plugins/GeneratedCustomActivity/)
    -   [FormBaseFromConditionAsync](https://api.workflowengine.io/core/OptimaJet.Workflow.Plugins.Activity/FormBaseFromConditionAsync/)

## Constructors

`public FormBase()` 

Initializes a new instance of [FormBase](https://api.workflowengine.io/core/OptimaJet.Workflow.Core/FormBase/).

## Properties

`public virtual bool Disabled { get; set; }` 

Gets or sets a value indicating whether this form is excluded from the custom activity or condition metadata exposed to the workflow designer.

`public virtual string Type { get; set; }` 

Gets or sets the form type identifier.

`public virtual string Title { get; set; }` 

Gets or sets the human-readable title for the form.

`public virtual string Template { get; set; }` 

Gets or sets the form template name used by UI renderers.

`public virtual List<CodeActionParameterDefinition> Parameters { get; set; }` 

Gets or sets the form parameter definitions.

`public virtual Dictionary<string, object> DefaultValues { get; set; }` 

Gets or sets form-specific default values.

## Methods

`public abstract Task ExecutionAsync(WorkflowRuntime runtime, ProcessInstance processInstance, Dictionary<string, string> parameters, CancellationToken token)` 

Executes the form operation during normal workflow execution.

### Parameters

| Name | Type | Description |
| --- | --- | --- |
| `runtime` | `WorkflowRuntime` | The [WorkflowRuntime](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Runtime/WorkflowRuntime/) invoking the execution. |
| `processInstance` | `ProcessInstance` | The current [ProcessInstance](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/ProcessInstance/). |
| `parameters` | `Dictionary<String, String>` | Runtime parameter values for the executed form operation, keyed by parameter name. |
| `token` | `CancellationToken` | The [CancellationToken](https://learn.microsoft.com/dotnet/api/system.threading.cancellationtoken) passed from the execution pipeline. |

### Returns

| Type | Description |
| --- | --- |
| `Task` | A [Task](https://learn.microsoft.com/dotnet/api/system.threading.tasks.task) that represents the asynchronous execution. |

`public abstract Task PreExecutionAsync(WorkflowRuntime runtime, ProcessInstance processInstance, Dictionary<string, string> parameters, CancellationToken token)` 

Executes the form operation during pre-execution simulation.

### Parameters

| Name | Type | Description |
| --- | --- | --- |
| `runtime` | `WorkflowRuntime` | The [WorkflowRuntime](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Runtime/WorkflowRuntime/) invoking the simulation. |
| `processInstance` | `ProcessInstance` | The current [ProcessInstance](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/ProcessInstance/). |
| `parameters` | `Dictionary<String, String>` | Runtime parameter values for the simulated operation, keyed by parameter name. |
| `token` | `CancellationToken` | The [CancellationToken](https://learn.microsoft.com/dotnet/api/system.threading.cancellationtoken) passed from the execution pipeline. |

### Returns

| Type | Description |
| --- | --- |
| `Task` | A [Task](https://learn.microsoft.com/dotnet/api/system.threading.tasks.task) that represents the asynchronous simulation. |

## Fields

`public static readonly string CustomTypeAnnotationName` 

Gets the annotation key used to store a form custom type.

## Remarks

To implement a custom workflow activity, derive from [ActivityBase](https://api.workflowengine.io/core/OptimaJet.Workflow.Core/ActivityBase/) instead of this class. [ActivityBase](https://api.workflowengine.io/core/OptimaJet.Workflow.Core/ActivityBase/) adds the metadata and rules required to display, configure, and save an activity node in the workflow designer. Direct inheritance from [FormBase](https://api.workflowengine.io/core/OptimaJet.Workflow.Core/FormBase/) is intended only for specialized form-based extension points, such as custom condition editors, that do not represent activity nodes on the scheme canvas.

[Previous Extensions](https://api.workflowengine.io/core/OptimaJet.Workflow.Core/Extensions/) [Next PersistenceProviderId](https://api.workflowengine.io/core/OptimaJet.Workflow.Core/PersistenceProviderId/)