# Index

{% hint style="warning" %}
The `Hand` class automatically instantiates the `Index` class for you.
{% endhint %}

```csharp
public class Index : Finger
```

Inherits [Finger ](/api-reference/finger.md)class.

### Constructors

| Name                                                                                                                  | Description                                                                         |
| --------------------------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------- |
| Index(Dictionary<[FingerJointType](/api-reference/fingerjointtype.md), [FingerJoint](/api-reference/fingerjoint.md)>) | Creates a new Index object with the specified finger joint types and finger joints. |

### Properties

| Name | Type                                         | Description                                                 |
| ---- | -------------------------------------------- | ----------------------------------------------------------- |
| MCP  | [FingerJoint](/api-reference/fingerjoint.md) | Read-Only. The index finger metacarpophalangeal joint.      |
| PIP  | [FingerJoint](/api-reference/fingerjoint.md) | Read-Only. The index finger proximal interphalangeal joint. |
| DIP  | [FingerJoint](/api-reference/fingerjoint.md) | Read-Only. The index finger distal interphalangeal joint.   |
| Tip  | [FingerJoint](/api-reference/fingerjoint.md) | Read-Only. The index finger tip joint.                      |

### Example

The example shows how to manage an index finger with the `Index` class.

#### Create an index finger with a constructor

```csharp
// Create an index tip joint with the specified 2D position and 
// 3D position.
FingerJoint indexTip = new FingerJoint
(
    FingerJointType.IndexTip, 
    new Vector2(3, 3), 
    new Vector3(0.3f, 0.3f, 0.3f),
    new Quaternion()
);

// Create an index DIP joint with the specified 2D position and 
// 3D position.
FingerJoint indexDIP = new FingerJoint
(
    FingerJointType.IndexDIP,
    new Vector2(3, 3),
    new Vector3(0.3f, 0.3f, 0.3f),
    new Quaternion()
);

 // Create an index finger with the specified index joints.
 Index index = new Index
 (
     new Dictionary<FingerJointType, FingerJoint> 
     {
         { FingerJointType.IndexTip, indexTip },
         { FingerJointType.IndexDIP, indexDIP }
     }
 );
```

#### Get joint information from an index finger

```csharp
// Get index Tip joint.
FingerJoint indexTipNew = index.Tip;
```


---

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