The function returns a length, in bytes, of the key of the specified element. 
- Parameters
 - 
  
    | [in] | hMapIter | is a handle to the iterator bound with the specified element.  | 
  
   
- Returns
 - The function returns a length, in bytes, of the key bound with the specified element. On failure the function returns (size_t) -1, use GetLastChsvError to get extended error information. 
 
- See also
 - MapGetKeyFromIter;
MapGetDataFromIter;
MapGetDataSizeFromIter.