How to: Convert from a STL/CLR Container to a .NET Collection
This topic shows how to convert STL/CLR containers to their equivalent .NET collections. As an example, we show how to convert a STL/CLR vector to a .NET ICollection<T> and how to convert a STL/CLR map to a .NET IDictionary<TKey, TValue>, but the procedure is similar for all collections and containers.
To create a collection from a container
Use one of the following methods:
To convert part of a container, call the make_collection function, and pass the begin iterator and end iterator of the STL/CLR container to be copied into the .NET collection. This template function takes an STL/CLR iterator as a template argument. The first example demonstrates this method.
To convert an entire container, cast the container to an appropriate .NET collection interface or interface collection. The second example demonstrates this method.
Example
In this example, we create a STL/CLR vector and add 5 elements to it. Then, we create a .NET collection by calling the make_collection function. Finally, we display the contents of the newly created collection.
// cliext_convert_vector_to_icollection.cpp
// compile with: /clr
#include <cliext/adapter>
#include <cliext/vector>
using namespace cliext;
using namespace System;
using namespace System::Collections::Generic;
int main(array<System::String ^> ^args)
{
cliext::vector<int> primeNumbersCont;
primeNumbersCont.push_back(2);
primeNumbersCont.push_back(3);
primeNumbersCont.push_back(5);
primeNumbersCont.push_back(7);
primeNumbersCont.push_back(11);
System::Collections::Generic::ICollection<int> ^iColl =
make_collection<cliext::vector<int>::iterator>(
primeNumbersCont.begin() + 1,
primeNumbersCont.end() - 1);
Console::WriteLine("The contents of the System::Collections::Generic::ICollection are:");
for each (int i in iColl)
{
Console::WriteLine(i);
}
}
The contents of the System::Collections::Generic::ICollection are: 3 5 7
In this example, we create a STL/CLR map and add 5 elements to it. Then, we create a .NET IDictionary<TKey, TValue> and assign the map directly to it. Finally, we display the contents of the newly created collection.
// cliext_convert_map_to_idictionary.cpp
// compile with: /clr
#include <cliext/adapter>
#include <cliext/map>
using namespace cliext;
using namespace System;
using namespace System::Collections::Generic;
int main(array<System::String ^> ^args)
{
cliext::map<float, int> ^aMap = gcnew cliext::map<float, int>;
aMap->insert(cliext::make_pair<float, int>(42.0, 42));
aMap->insert(cliext::make_pair<float, int>(13.0, 13));
aMap->insert(cliext::make_pair<float, int>(74.0, 74));
aMap->insert(cliext::make_pair<float, int>(22.0, 22));
aMap->insert(cliext::make_pair<float, int>(0.0, 0));
System::Collections::Generic::IDictionary<float, int> ^iDict = aMap;
Console::WriteLine("The contents of the IDictionary are:");
for each (KeyValuePair<float, int> ^kvp in iDict)
{
Console::WriteLine("Key: {0:F} Value: {1}", kvp->Key, kvp->Value);
}
}
The contents of the IDictionary are: Key: 0.00 Value: 0 Key: 13.00 Value: 13 Key: 22.00 Value: 22 Key: 42.00 Value: 42 Key: 74.00 Value: 74
See Also
Tasks
How to: Convert from a .NET Collection to a STL/CLR Container