# Interface IParameterBuilder

OptimaJet.Workflow.Core.Model.Builder.IParameterBuilder

Provides fluent configuration for an explicit process parameter in a [ProcessDefinition](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/ProcessDefinition/).

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

```csharp
public interface IParameterBuilder : IProcessDefinitionBuilder
```

## Type Hierarchy

-   IParameterBuilder Current type
    -   Base interfaces
        -   [IProcessDefinitionBuilder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/IProcessDefinitionBuilder/)

## Methods

`IParameterBuilder Ref(out ParameterDefinition parameterDefinition)` 

Assigns the current [ParameterDefinition](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/ParameterDefinition/) to `parameterDefinition`.

### Parameters

| Name | Type | Description |
| --- | --- | --- |
| `parameterDefinition` | `ParameterDefinition` | Receives the [ParameterDefinition](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/ParameterDefinition/) being configured. |

### Returns

| Type | Description |
| --- | --- |
| `IParameterBuilder` | The current [IParameterBuilder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/IParameterBuilder/) instance for method chaining. |

`IParameterBuilder Name(string name)` 

Sets the process parameter name of the current [ParameterDefinition](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/ParameterDefinition/).

### Parameters

| Name | Type | Description |
| --- | --- | --- |
| `name` | `String` | The process parameter name. |

### Returns

| Type | Description |
| --- | --- |
| `IParameterBuilder` | The current [IParameterBuilder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/IParameterBuilder/) instance for method chaining. |

`IParameterBuilder Purpose(ParameterPurpose purpose)` 

Sets [ParameterDefinition.Purpose](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/ParameterDefinition/) for the current process parameter.

### Parameters

| Name | Type | Description |
| --- | --- | --- |
| `purpose` | `ParameterPurpose` | The [ParameterPurpose](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/ParameterPurpose/) that controls how Workflow Engine manages and stores the parameter. |

### Returns

| Type | Description |
| --- | --- |
| `IParameterBuilder` | The current [IParameterBuilder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/IParameterBuilder/) instance for method chaining. |

### Exceptions

| Type | Description |
| --- | --- |
| `InvalidOperationException` | `purpose` is [ParameterPurpose.System](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/ParameterPurpose/). |

### Remarks

Setting `purpose` to [ParameterPurpose.Temporary](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/ParameterPurpose/) clears [ParameterDefinition.InitialValue](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/ParameterDefinition/).

`IParameterBuilder Type(Type type)` 

Sets [ParameterDefinition.Type](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/ParameterDefinition/) for the current process parameter.

### Parameters

| Name | Type | Description |
| --- | --- | --- |
| `type` | `Type` | The CLR [Type](https://learn.microsoft.com/dotnet/api/system.type) used for parameter values. |

### Returns

| Type | Description |
| --- | --- |
| `IParameterBuilder` | The current [IParameterBuilder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/IParameterBuilder/) instance for method chaining. |

### Exceptions

| Type | Description |
| --- | --- |
| `InvalidOperationException` | The existing [ParameterDefinition.InitialValue](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/ParameterDefinition/) cannot be deserialized as `type`. |

`IParameterBuilder InitialValue(string initialValue)` 

Sets [ParameterDefinition.InitialValue](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/ParameterDefinition/) from its stored string representation.

### Parameters

| Name | Type | Description |
| --- | --- | --- |
| `initialValue` | `String` | The value to store. For a parameter whose [ParameterDefinition.Type](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/ParameterDefinition/) is not [string](https://learn.microsoft.com/dotnet/api/system.string), the value must be valid JSON that can be deserialized as that type. |

### Returns

| Type | Description |
| --- | --- |
| `IParameterBuilder` | The current [IParameterBuilder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/IParameterBuilder/) instance for method chaining. |

### Exceptions

| Type | Description |
| --- | --- |
| `InvalidOperationException` | The current [ParameterDefinition.Purpose](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/ParameterDefinition/) is not [ParameterPurpose.Persistence](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/ParameterPurpose/), or `initialValue` cannot be deserialized as the current [ParameterDefinition.Type](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/ParameterDefinition/). |

`IParameterBuilder InitialValue(object initialValue)` 

Serializes `initialValue` and stores the result in [ParameterDefinition.InitialValue](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/ParameterDefinition/).

### Parameters

| Name | Type | Description |
| --- | --- | --- |
| `initialValue` | `Object` | The value to serialize. Its runtime type must be compatible with the current [ParameterDefinition.Type](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/ParameterDefinition/). |

### Returns

| Type | Description |
| --- | --- |
| `IParameterBuilder` | The current [IParameterBuilder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/IParameterBuilder/) instance for method chaining. |

### Exceptions

| Type | Description |
| --- | --- |
| `InvalidOperationException` | The current [ParameterDefinition.Purpose](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/ParameterDefinition/) is not [ParameterPurpose.Persistence](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/ParameterPurpose/), or `initialValue` is not an instance of the current [ParameterDefinition.Type](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/ParameterDefinition/). |

`IParameterBuilder ClearInitialValue()` 

Clears [ParameterDefinition.InitialValue](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/ParameterDefinition/) for the current process parameter.

### Returns

| Type | Description |
| --- | --- |
| `IParameterBuilder` | The current [IParameterBuilder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/IParameterBuilder/) instance for method chaining. |

[Previous IInlineActivityBuilder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/IInlineActivityBuilder/) [Next IProcessDefinitionBuilder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/IProcessDefinitionBuilder/)