Thread: passing HWND to STL map

Hi,

I’m trying to pass a HWND type to a STL map container.
I’m using like a void * to pass that parameter.
I’ve coded like this,

Code:

      Void fun (HWND hOwner, LPCTSTR str, HWND hValue)
     {
       map<const void*, std::string, void *> m1;
       m1.insert(make_pair(hOwner,str),hValue);    //Line 2
    }

I’m getting a compile time error ( Error Code C2664) in line 2.
Kindly guide me how to implement this.

Hi,

I didn't post the error message because, it had a very lengthy description.
So, hope the error number would be better to represent it.
And you are right that my explanations are not clear to help a person to understand the scenario.

My requirement is to store two values of type HWND and a string value in a map. The key should be a paired value of a HWND 1 and a string, the value type is HWND 2. I tried to do this using a void* pointer. But I got a compiler error about the improper conversion.

Could you kindly guide me how to do a type cast for HWND type to store it in STL map?

If you want the key to be a paired value of HWND and string, you should define the map as:

Code:

std::map<std::pair<HWND, std::string>, std::string>

You could also create your own struct to pair the key together instead of std::pair.

There is no need to typecast HWND to store it in a map. It will work just as it is.

To insert, you will need to use make_pair twice. Once to pair the HWND and string to form the key, and then again to pair that result with the string value.