## DropDownItemCollection class


A collection of strings that represent all the items in a drop-down form field. To learn more, visit the [Working with Fields](https://docs.aspose.com/words/cpp/working-with-fields/) documentation article.

```cpp
class DropDownItemCollection : public System::Collections::Generic::IEnumerable<System::String>,
                               public IComplexAttr
```

## Methods

| Method | Description |
| --- | --- |
| [Add](./add/)(const System::String\&) | Adds a string to the end of the collection. |
| [begin](./begin/)() |  |
| [begin](./begin/)() const |  |
| [cbegin](./cbegin/)() const |  |
| [cend](./cend/)() const |  |
| [Clear](./clear/)() | Removes all elements from the collection. |
| [Contains](./contains/)(const System::String\&) | Determines whether the collection contains the specified value. |
| [end](./end/)() |  |
| [end](./end/)() const |  |
| [get_Count](./get_count/)() | Gets the number of elements contained in the collection. |
| [GetEnumerator](./getenumerator/)() override | Returns an enumerator object that can be used to iterate over all items in the collection. |
| [GetType](./gettype/)() const override |  |
| [idx_get](./idx_get/)(int32_t) | Gets or sets the element at the specified index. |
| [idx_set](./idx_set/)(int32_t, const System::String\&) | Gets or sets the element at the specified index. |
| [IndexOf](./indexof/)(const System::String\&) | Returns the zero-based index of the specified value in the collection. |
| [Insert](./insert/)(int32_t, const System::String\&) | Inserts a string into the collection at the specified index. |
| [Is](./is/)(const System::TypeInfo\&) const override |  |
| [Remove](./remove/)(const System::String\&) | Removes the specified value from the collection. |
| [RemoveAt](./removeat/)(int32_t) | Removes a value at the specified index. |
| static [Type](./type/)() |  |
| [virtualizeBeginConstIterator](./virtualizebeginconstiterator/)() const override |  |
| [virtualizeBeginIterator](./virtualizebeginiterator/)() override |  |
| [virtualizeEndConstIterator](./virtualizeendconstiterator/)() const override |  |
| [virtualizeEndIterator](./virtualizeenditerator/)() override |  |
## Typedefs

| Typedef | Description |
| --- | --- |
| [const_iterator](./const_iterator/) |  |
| [iterator](./iterator/) |  |
| [iterator_holder_type](./iterator_holder_type/) |  |
| [virtualized_iterator](./virtualized_iterator/) |  |
| [virtualized_iterator_element](./virtualized_iterator_element/) |  |

## Examples



Shows how to insert a combo box field, and edit the elements in its item collection. 
```cpp
auto doc = System::MakeObject<Aspose::Words::Document>();
auto builder = System::MakeObject<Aspose::Words::DocumentBuilder>(doc);

// Insert a combo box, and then verify its collection of drop-down items.
// In Microsoft Word, the user will click the combo box,
// and then choose one of the items of text in the collection to display.
System::ArrayPtr<System::String> items = System::MakeArray<System::String>({u"One", u"Two", u"Three"});
System::SharedPtr<Aspose::Words::Fields::FormField> comboBoxField = builder->InsertComboBox(u"DropDown", items, 0);
System::SharedPtr<Aspose::Words::Fields::DropDownItemCollection> dropDownItems = comboBoxField->get_DropDownItems();

ASSERT_EQ(3, dropDownItems->get_Count());
ASSERT_EQ(u"One", dropDownItems->idx_get(0));
ASSERT_EQ(1, dropDownItems->IndexOf(u"Two"));
ASSERT_TRUE(dropDownItems->Contains(u"Three"));

// There are two ways of adding a new item to an existing collection of drop-down box items.
// 1 -  Append an item to the end of the collection:
dropDownItems->Add(u"Four");

// 2 -  Insert an item before another item at a specified index:
dropDownItems->Insert(3, u"Three and a half");

ASSERT_EQ(5, dropDownItems->get_Count());

// Iterate over the collection and print every element.
{
    System::SharedPtr<System::Collections::Generic::IEnumerator<System::String>> dropDownCollectionEnumerator = dropDownItems->GetEnumerator();
    while (dropDownCollectionEnumerator->MoveNext())
    {
        std::cout << dropDownCollectionEnumerator->get_Current() << std::endl;
    }
}

// There are two ways of removing elements from a collection of drop-down items.
// 1 -  Remove an item with contents equal to the passed string:
dropDownItems->Remove(u"Four");

// 2 -  Remove an item at an index:
dropDownItems->RemoveAt(3);

ASSERT_EQ(3, dropDownItems->get_Count());
ASSERT_FALSE(dropDownItems->Contains(u"Three and a half"));
ASSERT_FALSE(dropDownItems->Contains(u"Four"));

doc->Save(get_ArtifactsDir() + u"FormFields.DropDownItemCollection.html");

// Empty the whole collection of drop-down items.
dropDownItems->Clear();
```

## See Also

* Namespace [Aspose::Words::Fields](../)
* Library [Aspose.Words for C++](../../)