> For the complete documentation index, see [llms.txt](https://docs.wisej.com/api/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.wisej.com/api/v3.1/wisej.web/lists-and-grids/checkedlistbox/wisej.web.checkedlistbox.objectcollection.md).

# CheckedListBox.ObjectCollection

Namespace: **Wisej.Web**

Assembly: **Wisej.Framework** (3.1.0.0)

* [ObjectCollection](/api/v3.1/wisej.web/lists-and-grids/listbox/wisej.web.listbox.objectcollection.md)
  * [ObjectCollection](/api/v3.1/wisej.web/lists-and-grids/checkedlistbox/wisej.web.checkedlistbox.objectcollection.md)

Represents the collection of items in a [CheckedListBox](/api/v3.1/wisej.web/lists-and-grids/checkedlistbox.md).

{% tabs %}
{% tab title="C#" %}

```csharp
public class ObjectCollection : ObjectCollection
```

{% endtab %}

{% tab title="VB.NET" %}

```visual-basic
Public Class ObjectCollection
    Inherits ObjectCollection
```

{% endtab %}
{% endtabs %}

## Methods

### ![](/files/QmRDluociuQ34KzBtOjf)Add(item)

Adds an item to the list of items for a [ListBox](/api/v3.1/wisej.web/lists-and-grids/listbox.md).

| Parameter | Type                                                                | Description                                               |
| --------- | ------------------------------------------------------------------- | --------------------------------------------------------- |
| **item**  | [Object](https://docs.microsoft.com/en-us/dotnet/api/system.object) | An object representing the item to add to the collection. |

**Returns:** [Int32](https://docs.microsoft.com/en-us/dotnet/api/system.int32). The zero-based index of the item in the collection.

**Throws:**

* [ArgumentNullException](https://docs.microsoft.com/en-us/dotnet/api/system.argumentnullexception) The *item* parameter was null.

### ![](/files/QmRDluociuQ34KzBtOjf)Add(item, isChecked)

Adds an item to the list of items for a [CheckedListBox](/api/v3.1/wisej.web/lists-and-grids/checkedlistbox.md).

| Parameter     | Type                                                                  | Description                                               |
| ------------- | --------------------------------------------------------------------- | --------------------------------------------------------- |
| **item**      | [Object](https://docs.microsoft.com/en-us/dotnet/api/system.object)   | An object representing the item to add to the collection. |
| **isChecked** | [Boolean](https://docs.microsoft.com/en-us/dotnet/api/system.boolean) | True to check the item.                                   |

**Returns:** [Int32](https://docs.microsoft.com/en-us/dotnet/api/system.int32). The zero-based index of the item in the collection.

**Throws:**

* [ArgumentNullException](https://docs.microsoft.com/en-us/dotnet/api/system.argumentnullexception) The *item* parameter was null.

### ![](/files/QmRDluociuQ34KzBtOjf)Add(item, check)

Adds an item to the list of items for a [CheckedListBox](/api/v3.1/wisej.web/lists-and-grids/checkedlistbox.md).

| Parameter | Type                                                                   | Description                                               |
| --------- | ---------------------------------------------------------------------- | --------------------------------------------------------- |
| **item**  | [Object](https://docs.microsoft.com/en-us/dotnet/api/system.object)    | An object representing the item to add to the collection. |
| **check** | [CheckState](/api/v3.1/wisej.web/enumerations/wisej.web.checkstate.md) | The check state for the new item.                         |

**Returns:** [Int32](https://docs.microsoft.com/en-us/dotnet/api/system.int32).

### ![](/files/QmRDluociuQ34KzBtOjf)AddRange(items)

Adds a collection of items to the list.

| Parameter | Type                                                                    | Description                             |
| --------- | ----------------------------------------------------------------------- | --------------------------------------- |
| **items** | [Object\[\]](https://docs.microsoft.com/en-us/dotnet/api/system.object) | Collection of items to add to the list. |

### ![](/files/QmRDluociuQ34KzBtOjf)Clear()

Removes all items from the [CheckedListBox](/api/v3.1/wisej.web/lists-and-grids/checkedlistbox.md) control.

### ![](/files/QmRDluociuQ34KzBtOjf)Insert(index, item)

Inserts an item into the collection at the specified index.

| Parameter | Type                                                                | Description                                               |
| --------- | ------------------------------------------------------------------- | --------------------------------------------------------- |
| **index** | [Int32](https://docs.microsoft.com/en-us/dotnet/api/system.int32)   | The zero-based index location where the item is inserted. |
| **item**  | [Object](https://docs.microsoft.com/en-us/dotnet/api/system.object) | An object representing the item to insert.                |

**Throws:**

* [ArgumentNullException](https://docs.microsoft.com/en-us/dotnet/api/system.argumentnullexception) The *item* was null.
* [ArgumentOutOfRangeException](https://docs.microsoft.com/en-us/dotnet/api/system.argumentoutofrangeexception) The *index* was less than zero; or the *index* was greater than the count of items in the collection.

### ![](/files/QmRDluociuQ34KzBtOjf)Insert(index, item, check)

Inserts an item into the collection at the specified index.

| Parameter | Type                                                                   | Description                                               |
| --------- | ---------------------------------------------------------------------- | --------------------------------------------------------- |
| **index** | [Int32](https://docs.microsoft.com/en-us/dotnet/api/system.int32)      | The zero-based index location where the item is inserted. |
| **item**  | [Object](https://docs.microsoft.com/en-us/dotnet/api/system.object)    | An object representing the item to insert.                |
| **check** | [CheckState](/api/v3.1/wisej.web/enumerations/wisej.web.checkstate.md) | The check state for the new item.                         |

**Throws:**

* [ArgumentNullException](https://docs.microsoft.com/en-us/dotnet/api/system.argumentnullexception) The *item* was null.
* [ArgumentOutOfRangeException](https://docs.microsoft.com/en-us/dotnet/api/system.argumentoutofrangeexception) The *index* was less than zero; or the *index* was greater than the count of items in the collection.

### ![](/files/QmRDluociuQ34KzBtOjf)RemoveAt(index)

Removes an item from the [ListBox](/api/v3.1/wisej.web/lists-and-grids/listbox.md) at the specified index.

| Parameter | Type                                                              | Description                      |
| --------- | ----------------------------------------------------------------- | -------------------------------- |
| **index** | [Int32](https://docs.microsoft.com/en-us/dotnet/api/system.int32) | The index of the item to remove. |

**Throws:**

* [ArgumentOutOfRangeException](https://docs.microsoft.com/en-us/dotnet/api/system.argumentoutofrangeexception) The *index* parameter was less than zero, or the *index* parameter was greater than or equal to the count of items in the collection.


---

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