Platform::Collections::Vector Class

Represents a sequential collection of objects that can be individually accessed by index.

Syntax

template <typename T, typename E>  
   ref class Vector sealed;  

Parameters

T
The type of the elements contained in the Vector object.

E
Specifies a binary predicate for testing equality with values of type T. The default value is std::equal_to<T>.

Remarks

Allowed types are:

  1. integers

  2. interface class ^

  3. public ref class^

  4. value struct

  5. public enum class

    The Vector class is the C++ concrete implementation of the Windows::Foundation::Collections::IVector interface.

    If you attempt to use a Vector type in a public return value or parameter, compiler error C3986 will be raised. You can fix the error by changing the parameter or return value type to Windows::Foundation::Collections::IVector. For more information, see Collections (C++/CX).

Members

Public Constructors

Name Description
Vector::Vector Initializes a new instance of the Vector class.

Public Methods

Name Description
Vector::Append Inserts the specified item after the last item in the current Vector.
Vector::Clear Deletes all the elements in the current Vector.
Vector::First Returns an iterator that specifies the first element in the Vector.
Vector::GetAt Retrieves the element of the current Vector that is identifed by the specified index.
Vector::GetMany Retrieves a sequence of items from the current Vector, starting at the specified index.
Vector::GetView Returns a read-only view of a Vector; that is, a Platform::Collections::VectorView.
Vector::IndexOf Searches for the specified item in the current Vector, and if found, returns the index of the item.
Vector::InsertAt Inserts the specified item into the current Vector after the element identified by the specified index.
Vector::ReplaceAll Deletes the elements in the current Vector and then inserts the elements from the specified array.
Vector::RemoveAt Deletes the element identified by the specified index from the current Vector.
Vector::RemoveAtEnd Deletes the element at the end of the current Vector.
Vector::SetAt Assigns the specified value to the element in the current Vector that is identified by the specified index.
Vector::Size Returns the number of elements in the current Vector object.

Events

Name Description
event Windows::Foundation::Collection::VectorChangedEventHandler<T>^ VectorChanged Occurs when the Vector changes.

Inheritance Hierarchy

Vector

Requirements

Header: collection.h

Namespace: Platform::Collections

Vector::Append Method

Inserts the specified item after the last item in the current Vector.

Syntax

virtual void Append(T item);  

Parameters

index
The item to insert into the Vector. The type of item is defined by the T typename.

Vector::Clear Method

Deletes all the elements in the current Vector.

Syntax

virtual void Clear();  

Vector::First Method

Returns an iterator that points to the first element in the Vector.

Syntax


virtual Windows::Foundation::Collections::IIterator <T>^ First();  

Return Value

An iterator that points to the first element in the Vector.

Remarks

A convenient way to hold the iterator returned by First() is to assign the return value to a variable that is declared with the auto type deduction keyword. For example, auto x = myVector->First();. This iterator knows the length of the collection.

When you need a pair of iterators to pass to an STL function, use the free functions Windows::Foundation::Collections::begin and Windows::Foundation::Collections::end

Vector::GetAt Method

Retrieves the element of the current Vector that is identifed by the specified index.

Syntax

virtual T GetAt(unsigned int index);  

Parameters

index
A zero-based, unsigned integer that specifies a particular element in the Vector object.

Return Value

The element specified by the index parameter. The element type is defined by the T typename.

Vector::GetMany Method

Retrieves a sequence of items from the current Vector, starting at the specified index, and copies them into the caller-allocated array.

Syntax

virtual unsigned int GetMany(
    unsigned int startIndex, 
    Platform::WriteOnlyArray<T>^ dest);  

Parameters

startIndex
The zero-based index of the start of the items to retrieve.

dest
A caller-allocated array of items that begin at the element specified by startIndex and end at the last element in the Vector.

Return Value

The number of items retrieved.

Remarks

This function is not intended for use directly by client code. It is used internally in the to_vector Function to enable efficient conversion of Platform::Vector intances to std::vector instances.

Vector::GetView Method

Returns a read-only view of a Vector; that is, an IVectorView.

Syntax

Windows::Foundation::Collections::IVectorView<T>^ GetView();  

Return Value

An IVectorView object.

Vector::IndexOf Method

Searches for the specified item in the current Vector, and if found, returns the index of the item.

Syntax


virtual bool IndexOf(T value, unsigned int* index);  

Parameters

value
The item to find.

index
The zero-based index of the item if parameter value is found; otherwise, 0.

The index parameter is 0 if either the item is the first element of the Vector or the item was not found. If the return value is true, the item was found and it is the first element; otherwise, the item was not found.

Return Value

true if the specified item is found; otherwise, false.

Remarks

IndexOf uses std::find_if to find the item. Custom element types should therefore overload the == and != operator in order to enable the equality comparisons that find_if requires.

Vector::InsertAt Method

Inserts the specified item into the current Vector after the element identified by the specified index.

Syntax

virtual void InsertAt(unsigned int index, T item)  

Parameters

index
A zero-based, unsigned integer that specifies a particular element in the Vector object.

item
An item to insert into the Vector after the element specified by index. The type of item is defined by the T typename.

Vector::RemoveAt Method

Deletes the element identified by the specified index from the current Vector.

Syntax

virtual void RemoveAt(unsigned int index);  

Parameters

index
A zero-based, unsigned integer that specifies a particular element in the Vector object.

Vector::RemoveAtEnd Method

Deletes the element at the end of the current Vector.

Syntax

virtual void RemoveAtEnd();  

Vector::ReplaceAll Method

Deletes the elements in the current Vector and then inserts the elements from the specified array.

Syntax

virtual void ReplaceAll(const ::Platform::Array<T>^ arr);  

Parameters

arr
An array of objects whose type is defined by the T typename.

Vector::SetAt Method

Assigns the specified value to the element in the current Vector that is identified by the specified index.

Syntax

virtual void SetAt(unsigned int index, T item);  

Parameters

index
A zero-based, unsigned integer that specifies a particular element in the Vector object.

item
The value to assign to the specified element. The type of item is defined by the T typename.

Vector::Size Method

Returns the number of elements in the current Vector object.

Syntax

virtual property unsigned int Size;  

Return Value

The number of elements in the current Vector.

Vector::Vector Constructor

Initializes a new instance of the Vector class.

Syntax

Vector();  

explicit Vector(unsigned int size);  
Vector( unsigned int size, T value);    
template <typename U> explicit Vector( const ::std::vector<U>& v);    
template <typename U> explicit Vector( std::vector<U>&& v);    

Vector( const T * ptr, unsigned int size);    
template <size_t N> explicit Vector(const T(&arr)[N]);    
template <size_t N> explicit Vector(const std::array<T, N>& a);   
explicit Vector(const Array<T>^ arr);  

template <typename InIt> Vector(InIt first, InIt last);   
Vector(std::initializer_list<T> il);  

Parameters

a
A std::array that will be used to initialize the Vector.

a
A Platform::Array that will be used to initialize the Vector.

InIt
The type of a collection of objects that is used to initialize the current Vector.

il
A std::initializer_list of objects of type T that will be used to initialize the Vector.

N
The number of elements in a collection of objects that is used to initialize the current Vector.

size
The number of elements in the Vector.

value
A value that is used to initialize each element in the current Vector.

v
An Lvalues and Rvalues to a std::vector that is used to initialize the current Vector.

ptr
Pointer to a std::vector that is used to initialize the current Vector.

arr
A Platform::Array object that is used to initialize the current Vector.

a
A std::array object that is used to initialize the current Vector.

first
The first element in a sequence of objects that are used to initialize the current Vector. The type of first is passed by means of perfect forwarding. For more information, see Rvalue Reference Declarator: &&.

last
The last element in a sequence of objects that are used to initialize the current Vector. The type of last is passed by means of perfect forwarding. For more information, see Rvalue Reference Declarator: &&.

See Also

Platform Namespace
Creating Windows Runtime Components in C++