> 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/wisej.web/editors/domainupdown/wisej.web.domainupdown.domainupdownitemcollection.md).

# DomainUpDown.DomainUpDownItemCollection

Namespace: **Wisej.Web**

Assembly: **Wisej.Framework** (4.0.0.0)

Encapsulates a collection of objects for use by the [DomainUpDown](/api/wisej.web/editors/domainupdown.md) class.

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

```csharp
public class DomainUpDownItemCollection : IList, ICollection, IEnumerable
```

{% endtab %}

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

```visual-basic
Public Class DomainUpDownItemCollection
    Inherits IList
    Implements ICollection, IEnumerable
```

{% endtab %}
{% endtabs %}

## Properties

### ![](/files/hsR4ok3152WyAf8J2C1u) Count

[Int32](https://docs.microsoft.com/dotnet/api/system.int32): Returns the number of items in the collection.

### ![](/files/hsR4ok3152WyAf8J2C1u) IsReadOnly

[Boolean](https://docs.microsoft.com/dotnet/api/system.boolean): Returns a value indicating whether this collection can be modified.

### ![](/files/hsR4ok3152WyAf8J2C1u) Item(index)

[Object](https://docs.microsoft.com/dotnet/api/system.object): Retrieves the item at the specified index within the collection.

**Throws:**

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

## Methods

### ![](/files/hsR4ok3152WyAf8J2C1u) Add(item)

Adds an object to the end of the collection.

| Parameter | Type                                                          | Description                                                                                                                        |
| --------- | ------------------------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------- |
| **item**  | [Object](https://docs.microsoft.com/dotnet/api/system.object) | The [Object](https://docs.microsoft.com/dotnet/api/system.object) to be added to the end of the collection. The value can be null. |

**Returns:** [Int32](https://docs.microsoft.com/dotnet/api/system.int32). The index at which the *item* has been added.

### ![](/files/hsR4ok3152WyAf8J2C1u) AddRange(items)

Adds a collection of objects to the end of the collection.

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

### ![](/files/hsR4ok3152WyAf8J2C1u) Clear()

Removes all items from the [DomainUpDown](/api/wisej.web/editors/domainupdown.md) control.

### ![](/files/hsR4ok3152WyAf8J2C1u) Contains(item)

Determines if the specified item is located within the collection.

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

**Returns:** [Boolean](https://docs.microsoft.com/dotnet/api/system.boolean). true if the item is located within the collection; otherwise, false.

### ![](/files/hsR4ok3152WyAf8J2C1u) GetEnumerator()

Returns an enumerator that can be used to iterate through the item collection.

**Returns:** [IEnumerator](https://docs.microsoft.com/dotnet/api/system.collections.ienumerator). A [IEnumerator](https://docs.microsoft.com/dotnet/api/system.collections.ienumerator) that represents the item collection.

### ![](/files/hsR4ok3152WyAf8J2C1u) IndexOf(item)

Retrieves the index within the collection of the specified item.

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

**Returns:** [Int32](https://docs.microsoft.com/dotnet/api/system.int32). The zero-based index where the item is located within the collection; otherwise, -1.

**Throws:**

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

### ![](/files/hsR4ok3152WyAf8J2C1u) Insert(index, item)

Inserts an element into the collection at the specified index.

| Parameter | Type                                                          | Description                                                                                         |
| --------- | ------------------------------------------------------------- | --------------------------------------------------------------------------------------------------- |
| **index** | [Int32](https://docs.microsoft.com/dotnet/api/system.int32)   | The zero-based index at which *item* should be inserted.                                            |
| **item**  | [Object](https://docs.microsoft.com/dotnet/api/system.object) | The [Object](https://docs.microsoft.com/dotnet/api/system.object) to insert. The value can be null. |

**Throws:**

* [ArgumentOutOfRangeException](https://docs.microsoft.com/dotnet/api/system.argumentoutofrangeexception)*index* is less than zero, or *index* is greater than number of items in the collection.

### ![](/files/hsR4ok3152WyAf8J2C1u) Remove(item)

Removes the first occurrence of a specific object from the collection.

| Parameter | Type                                                          | Description                                                                                                             |
| --------- | ------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------- |
| **item**  | [Object](https://docs.microsoft.com/dotnet/api/system.object) | The [Object](https://docs.microsoft.com/dotnet/api/system.object) to remove from the collection. The value can be null. |

### ![](/files/hsR4ok3152WyAf8J2C1u) RemoveAt(index)

Removes the element at the specified index of the collection.

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

**Throws:**

* [ArgumentOutOfRangeException](https://docs.microsoft.com/dotnet/api/system.argumentoutofrangeexception)*index* is less than zero; or *index* is equal to or greater than number of items in the collection.


---

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