Sending Email using MAPI - A COM DLL

• Download source files - 92.3 Kb
• Download demo project - 97.9 Kb

Introduction

During the software development, I have seen many applications that requires incorporating email support. I remember, once I was to develop an application, which sends emails at the specific time to specific people with the customized messages. For that I developed a COM service that used MAPI. MAPI, i.e. Messaging Application Programming Interface, is the standard messaging architecture and a complete set of functions and object-oriented interfaces. Here I have an Email component, a COM DLL, which is a set of messaging functions that helps you create messaging-enabled applications. This COM component uses Simple MAPI to achieve that.

Note: MAPI is used by various industry-standard e-mail clients, such as the Microsoft Exchange client, all versions of Microsoft Outlook and Outlook Express, including QUALCOMM Incorporated (Eudora) and Netscape Communications Corporation. So you can use this component with these client applications also.

Component Design

The CLSID of the Email component is CLSID_Mail and it has only one interface IMail with the interface ID IID_IMail.

CMail is the implementation class and contains following data members:

m_MAPILogon	Function pointer for MAPILogon
m_MAPISendMail	Function pointer for MAPISendMail
m_MAPISendDocuments	Function pointer for MAPISendDocuments
m_MAPIFindNext	Function pointer for MAPIFindNext
m_MAPIReadMail	Function pointer for MAPIReadMail
m_MAPIResolveName	Function pointer for MAPIResolveName
m_MAPIAddress	Function pointer for MAPIAddress
m_MAPILogoff	Function pointer for MAPILogoff
m_MAPIFreeBuffer	Function pointer for MAPIFreeBuffer
m_MAPIDetails	Function pointer for MAPIDetails
m_MAPISaveMail	Function pointer for MAPISaveMail

IMail have the following functions:

IsMapiInstalled	Checks if the MAPI is installed on the system. It searches Win.INI file for the MAPI key. If found it returns S_OK.
InitMapi	After checking the through IsMapiInstalled, it initializes the MAPI function pointers. Method should be called once before using the component.
put_strProfileName	Takes the name of the outlook profile name you are using to send the email.
put_strEmailAddress	Sets the recipient email address. You can specify more than one comma (,) separated recipient addresses.
put_strRecipient	Sets the name you want to specify for the recipients, sets the email names of the sender – it may be different from your specified profile email address.
put_strSubject	Sets the subject of the email.
get_strSubject	Returns the email subject.
put_strMessage	Sets email message text.
get_strMessage	Returns message text.
put_strAttachmentFilePath	Sets the email attachment with the full path like “c:\abc.txt”.
get_strAttachmentFilePath	Returns the path of email attachment.
put_strAttachmentFile	The display name of the attachment (Sample.txt), by default, it’s the same as that specified in put_strAttachmentFilePath.
get_strAttachmentFile	Returns the attachment file name.
Logon	Opens a new logon session if not already opened, using specified outlook profile, name and the profile password, you must logon before sending the email. I have set password to NULL assuming that the profile you will specify have NO password, but you can specify your own password. Automatically called by Send method.
Logoff	Logs off, and closes the session. Automatically called by Send method after sending the email.
Send	Sends the email, requires valid outlook profile name, recipient email address and a login session to send email.

Steps to execute the demo project

The demo project demonstrates the way you can use the component to send an email. In order to execute the demo project, the following settings are required:

Step 1: You must have some valid Output Express email account or create one named TestProfile.

You can create an email profile in Express from Tools>Accounts menu. This will open Internet Accounts property sheet. On the tab All, click the button Add and then Mail. A wizard will let you create an email account, specify the valid email address. For hotmail account, wizard automatically sets the names of email servers.

After successfully creating the account, select the account name from the list in All tab (for hotmail account, the default account name is Hotmail). Open account properties by pressing Properties button and change the account name from default name (say Hotmail) to TestProfile.

Step 2: Register the DLL

All COM DLLs required to be registered. After copying the DLL source code, you can register the DLL by right clicking the DLL and selecting Register DLL or Register COM component option, or simply by double clicking the DLL. Compiling the DLL code in Visual Studio will automatically register the DLL.

Step 3: Logged on to the net

Make sure you are logged on to the net. If not, outlook will fail to deliver the email, however, you can still check the composed email in your outbox.

How to send email?

After specifying the information in the dialog box, click the Send button. A warning message will be displayed, click Send button.

Note:The warning dialog is displayed because of the security constraints. If you want to get rid of this dialog box, then you will have to use Extended MAPI instead of simple MAPI.

Here is the method CTestEmailDlg::OnSend method, which is used to pass the user specified information to the email object and call the IMail::Send method after setting everything.

//##//##//////////////////////////////////////////////////////////////

///////////////////////////////////////////////
//
//  void CTestEmailDlg::OnSend() 
//
//    This module is called when send button is pressed and uses 
//Email COM DLL to send 

email - Aisha Ikram
// Note: dont forget to initialize COM library using CoInitialize(NULL);
//##//##////////////////////////////////////////////////////////////////////

///////////////////////////////////////////////

void CTestEmailDlg::OnSend() 
{
  UpdateData();
  try{
       
    CComPtr objMail;
        
    HRESULT hr;
    // make sure the DLL is registered
    hr = objMail.CoCreateInstance(CLSID_Mail);
    if(SUCCEEDED(hr))
    {
      if(hr== S_OK)
      {
        // profile name is compulsory, this is the outlook profile, 
        // i used "outlook express" as configuring it is easier than 
       // "MS outlook" make sure to specify the correct sender's address 
       // for this profile and make sure that outlook express is 
       //the default email client.
    
       if(m_strProfile.IsEmpty())
       {    
         AfxMessageBox("Please specify email profile name ");
         return;    
       }
                
       if(m_strTo.IsEmpty())
       {
         AfxMessageBox("Please specify recipient's email address ");
         return;
       }
       // by default, it's TestProfile, assumes that a profile with this 
       //name exists in outlook
       hr= objMail->put_strProfileName((_bstr_t)m_strProfile);
                
       hr = objMail->put_strSubject((_bstr_t)m_strSubject);
                
       // this is the email or set of email addresses (separated by ,)
       // which is actually used to send email            
       hr = objMail->put_strEmailAddress((_bstr_t)m_strTo);
                
       // recipient is just to show the display name
       hr = objMail->put_strRecipient((_bstr_t)m_strTo);
                
       hr = objMail->put_strAttachmentFilePath((_bstr_t)m_strAttachment);
                
       hr = objMail->put_strMessage((_bstr_t)m_strMessage);

       hr= objMail->Send();

       if(hr!=S_OK)
         AfxMessageBox("Error, make sure the info is correct");
       }//if
     } //if
   } // try
   catch(...)
   {
     AfxMessageBox("Error, make sure specified info is correct");
   }
}

Check the mail in the recipient inbox.

Where to use

This component can be extended to incorporate the functionalities like opening an existing inbox to read emails automatically from the inbox and composing new emails etc. It can be used to send emails automatically with customized user messages and attachments to specific people at particular time, especially while using some exe servers or NT services.

That's it. If there is any suggestions or comments you are most welcome. Your rating would help me evaluate the standard of my article.

Looking for a Class instead of a COM component?

I have also build a class CSMAPI, to use simple MAPI to send email, read and find a message and more is to be added. You can find this class, which you can use anywhere (either in win32, or MFC or ATL) and the demo project in MFC.

You can find all at my website (free code and articles website).