This method returns the standard values E_INVALIDARG, E_OUTOFMEMORY, E_UNEXPECTED, and E_FAIL, as well as the following:

S_OK

Indicates success.

When querying Message forms based on IMessageFormEx2with IMessageFormEx::GetMenuCapabilities, the behavior of the dwFlagsparameter differs from that used for Message forms created using IMessageFormEx. The changes are as follows:

• The top four bits of dwFlagsbecome "Region" bits, and the remaining 28 bits are treated as the "Menu Capability" bits.
  
  
• This approach provides 16 x 28 = 448 different Menu Capabilities ( IMessageFormExsupports a maximum of 32).
  
  
• The extended set of command bar capabilities introduced in Windows Mobile 6.5 are associated with Region 1. For a listing of the extended capabilities, see The Extended Set of Command Bar Capability Constantssection in Message Form Host Command Bar Capability Flags.
  
  
• The capabilities in Region 1 are named as MESSAGEFORMHOST2_CMDBARCAP2_xxx, and in Region 2 as MESSAGEFORMHOST2_CMDBARCAP3_xxx, etc.
  
  

For backward compatibility, the way to determine whether a Message Form supports the extended menu capabilities is as follows:

• When dwFlagshas any region bits set, but does not have any menu item bits set— IMessageFormEx::GetMenuCapabilitiesruns in an alternate mode known as Detection Mode.
  
  
• In Detection Mode, IMessageFormEx::GetMenuCapabilitiesreturns (in the * pdwEnableout parameter) a bitmask with all of the Menu Capability bits set to one if extended capability is supported, all bits set to zero if not.
  
  

For example, the call GetMenuCapabilites(0x10000000, &dwEnable)returns 0x1fffffffif the Message Form supports the extended menu capabilities, and 0x10000000if it does not.

The Messaging Application calls the Message Form with GetMenuCapabilitiespassing in a list of all the menu items that can possibly appear in the menu. This list is passed in the dwFlagsparameter and is a bitmask created by combining zero or more Message Form Host Command Bar Capability Flagsusing the bitwise OR. For example, use MESSAGEFORMHOST2_CMDBARCAP_CUT | MESSAGEFORMHOST2_CMDBARCAP_PASTEto include both the Cutand Pastemenu commands. GetMenuCapabilitiesreturns a second list that contains just those menu items that the add-in supports. The menu items that appear in the input list, but which are absent in the output list, appear grayed-out in the add-in's menu.