MFC Collection Utilities library

C++11 has provided support for range-based for loops. They allow iterating over the elements of a range without using an index.

std::vector<int> v = {1, 2, 3, 4, 5};
for(auto& e : v)
  e *= 2;

However, if you try the following MFC code you get some errors because the compiler is looking for a begin() and end() function that provides access to the first and last element of the range:

void func(CStringArray const & arr)
{
   for(auto const & str : arr)
   {
      // do something with str
   }
}

1>error C3312: no callable ‘begin’ function found for type ‘CStringArray’
1>error C3312: no callable ‘end’ function found for type ‘CStringArray’

MFC does not define such functions for its containers.

Enter MFC Collection Utilities

Tom Kirby-Green and I have developed a small open-source library that enables the use of all MFC collection types in range-based for loops. The library is called MFC Collection Utilities and is available on codeplex.

The library consists of a single header, called mfciterators.h, that you include in your MFC projects.

#include "mfciterators.h"

void func(CStringArray const & arr)
{
   for(auto const & str : arr)
   {
      // do something with str
   }
}

Compiler and collections support

The library works in Visual Studio 2012 (the first version of the C++ compiler that supports range-based for loops) or a newer version.

The library enables all the MFC collections, both template and non-template, to be used in range-based for loops. This means arrays, lists and maps. For maps you get access to the content through a key-value pair that has two fields: key and value.

Supported template collections

Supported non-template collections

Examples

CStringArray arr;
arr.Add("this");
arr.Add("is");
arr.Add("a");
arr.Add("sample");

for(auto & s : arr)
{
   s.MakeUpper();
}

class CFoo
{
public:
   int value;

   CFoo(int const v): value(v) {}
};

CTypedPtrList<CPtrList, CBar*> ptrlist;
ptrlist.AddTail(new CFoo(1));
ptrlist.AddTail(new CFoo(2));
ptrlist.AddTail(new CFoo(3));

for(auto & o : ptrlist)
   o->value *= 2;

CMap<int, int, CString, CString> map;

map.SetAt(1, "one");
map.SetAt(2, "two");
map.SetAt(3, "three");

for(auto & kvp : map)
{
   kvp.value.MakeUpper();
}

for(auto const & kvp : map)
{
   CString temp;
   temp.Format("key=%d, value=%s", kvp.key, kvp.value);
}

Download

Version 1.0 can be downloaded from codeplex from here.

For simpler installation you can use the available nuget package.

Let us know if you encounter any issues.