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winrt::vector_base struct template (C++/WinRT)

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A base class from which you can derive to implement your own custom non-observable general-purpose collection. For more info, and code examples, see Collections with C++/WinRT.

Syntax

template <typename D, typename T>
struct vector_base : vector_view_base<D, T, winrt::impl::collection_version>

Template parameters

typename D Your derived type name.

typename T The type of the elements in the vector_base.

Requirements

Minimum supported SDK: Windows SDK version 10.0.17763.0 (Windows 10, version 1809)

Namespace: winrt

Header: %WindowsSdkDir%Include<WindowsTargetPlatformVersion>\cppwinrt\winrt\base.h (included by default)

Member functions

Function Description
vector_base::Append function Appends an element to the end of the vector_base object.
vector_base::Clear function Removes all elements from the vector_base object.
vector_base::First function Retrieves an IIterator representing the first element in the vector_base object.
vector_base::GetAt function Retrieves the element at the specified index in the vector_base object.
vector_base::GetMany function Retrieves a collection of elements in the vector_base object beginning at the given index.
vector_base::GetView function Retrieves an immutable view of the vector_base object.
vector_base::IndexOf function Retrieves the index of a specified element in the vector_base object.
vector_base::InsertAt function Inserts an element at the specified index in the vector_base object.
vector_base::RemoveAt function Removes the element at the specified index in the vector_base object.
vector_base::RemoveAtEnd function Removes the last element from the vector_base object.
vector_base::ReplaceAll function Replaces all the elements in the vector_base object with the specified elements.
vector_base::SetAt function Sets the value of the element at the specified index in the vector_base object.
vector_base::Size function Retrieves the number of elements in the vector_base object.

Iterators

A vector_base is a range, and that range is defined by internal free functions (each of which retrieves an iterator) that are compatible with standard language features. Because of this, you can enumerate the elements in a vector_base object with a range-based for statement.

You can also retrieve an IIterator from the vector_base::First function, and use that to iterate through the elements in a vector_base object.

...
#include <iostream>
using namespace winrt;
using namespace Windows::Foundation::Collections;
...
struct MyVector :
    implements<MyVector, IVector<float>, IVectorView<float>, IIterable<float>>,
    winrt::vector_base<MyVector, float>
{
    auto& get_container() const noexcept
    {
        return m_values;
    }

    auto& get_container() noexcept
    {
        return m_values;
    }

private:
    std::vector<float> m_values{ 0.1f, 0.2f, 0.3f };
};
...
IVector<float> coll{ winrt::make<MyVector>() };

for (auto const& el : coll)
{
    std::wcout << el << std::endl;
}

IIterator<float> it{ coll.First() };
while (it.HasCurrent())
{
    std::wcout << it.Current() << std::endl;
    it.MoveNext();
}

vector_base::Append function

Appends an element to the end of the vector_base object.

Syntax

void Append(T const& value);

Parameters

value The element to append.

vector_base::Clear function

Removes all elements from the vector_base object.

Syntax

void Clear() noexcept;

vector_base::First function

Retrieves an IIterator representing the first element in the vector_base object.

Syntax

auto First();

Return value

An IIterator representing the first element in the vector_base object.

vector_base::GetAt function

Retrieves the element at the specified index in the vector_base object.

Syntax

T GetAt(uint32_t const index) const;

Parameters

index A zero-based element index.

Return value

The element at the specified index in the vector_base object.

vector_base::GetMany function

Retrieves a collection of elements in the vector_base object beginning at the given index.

Syntax

uint32_t GetMany(uint32_t const startIndex, array_view<T> values) const;

Parameters

startIndex A zero-based element index to start at.

values An array_view to copy the items into.

Return value

A value representing the number of elements retrieved.

vector_base::GetView function

Retrieves an immutable view of the vector_base object.

Syntax

winrt::Windows::Foundation::Collections::IVectorView<T> GetView() const noexcept;

Return value

An IVectorView containing an immutable view of the vector_base.

vector_base::IndexOf function

Retrieves the index of a specified element in the vector_base object.

Syntax

bool IndexOf(T const& value, uint32_t& index) const noexcept;

Parameters

value The element, in the vector_base object, to look for.

index The zero-based index of the element if the element is found, otherwise the number of elements in the vector_base object.

Return value

true if the element is found, otherwise false.

vector_base::InsertAt function

Inserts an element at the specified index in the vector_base object.

Syntax

void InsertAt(uint32_t const index, T const& value);

Parameters

index The zero-based index at which to insert the element.

value The element to insert.

vector_base::RemoveAt function

Removes the element at the specified index in the vector_base object.

Syntax

void RemoveAt(uint32_t const index);

Parameters

index The zero-based index of the element to remove.

vector_base::RemoveAtEnd function

Removes the last element from the vector_base object.

Syntax

void RemoveAtEnd();

vector_base::ReplaceAll function

Replaces all the elements in the vector_base object with the specified elements.

Syntax

void ReplaceAll(array_view<T const> value);

Parameters

value An array_view containing the new elements.

vector_base::SetAt function

Sets the value of the element at the specified index in the vector_base object.

Syntax

void SetAt(uint32_t const index, T const& value);

Parameters

index The zero-based index of the element whose value to set.

value The element value to set.

vector_base::Size function

Retrieves the number of elements in the vector_base object.

Syntax

uint32_t Size() const noexcept;

Return value

A value representing the number of elements in the vector_base object.

See also