Download/Retrieve Email from Gmail account in Delphi

In previous section, I introduced how to retrieve email over SSL connection. In this section, I will introduce how to download email from your Gmail account in Delphi.

Introduction

Gmail POP3 server address is pop.gmail.com. It requires SSL connection on 995 port, and you should use your Gmail email address as the user name for user authentication.

Gmail IMAP4 server address is imap.gmail.com. It requires SSL connection on 993 port, and you should use your Gmail email address as the user name for user authentication. For example: your email is gmailid@gmail.com, and then the user name should be gmailid@gmail.com.

To retrieve email from Gmail account, you need to enable POP3 or IMAP4 access in your gmail account settings.

Because Gmail POP3 server doesn’t work like normal POP3 server, it hides old emails automatically even the email was not deleted, so we suggest that you use IMAP4 protocol.

Server Port SSL Protocol
pop.gmail.com 995 SSL required Pop3
imap.gmail.com 993 SSL required Imap4 (recommended)

Important

If you got authentication error, you need to enable Allowing less secure apps or Sign in using App Passwords.

Another way is Gmail OAUH, please see Gmail IMAP OAUTH section.

Note

Remarks: All of examples in this section are based on first section: A simple Delphi project. To compile and run the following example codes successfully, please click here to learn how to create the test project and add reference to your project.

[Delphi Example - Retrieve email from Gmail account]

The following example codes demonstrate how to download email from Gmail account using IMAP4 protocol.

Because Gmail POP3 server doesn’t work like normal POP3 server, it hides old emails automatically even the email was not deleted, so we suggest that you use IMAP4 protocol.

Note

To get the full sample projects, please refer to Samples section.

unit Unit1;

interface

uses
    Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
    Dialogs, StdCtrls, EAGetMailObjLib_TLB; // Add EAGetMail unit

type
    TForm1 = class(TForm)
        Button1: TButton;
        procedure Button1Click(Sender: TObject);
    private
        { Private declarations }
    public
        { Public declarations }
    end;

const
    MailServerPop3 = 0;
    MailServerImap4 = 1;
    MailServerEWS = 2;
    MailServerDAV = 3;

var
    Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.Button1Click(Sender: TObject);
var
    oMail: IMail;
    oClient: TMailClient;
    oServer: TMailServer;
    oTools: TTools;
    infos: OleVariant;
    i, UBound, Count: integer;
    oInfo: IMailInfo;
    mailFolder: WideString;
    fileName: WideString;
begin
    try
        oTools := TTools.Create(Application);

        // Create a folder named "inbox" under
        // current directory to store the email files
        mailFolder := GetCurrentDir() + '\inbox';
        oTools.CreateFolder(mailFolder);

        oServer := TMailServer.Create(Application);

        // Gmail IMAP server address
        oServer.Server := 'imap.gmail.com';
        oServer.User := 'gmailid@gmail.com';
        oServer.Password := 'testpassword';
        oServer.Protocol := MailServerImap4;

        // Enable SSL connection
        oServer.SSLConnection := true;

        // Set 993 IMAP SSL Port
        oServer.Port := 993;

        oClient := TMailClient.Create(Application);
        oClient.LicenseCode := 'TryIt';

        oClient.Connect1(oServer.DefaultInterface);
        ShowMessage( 'Connected!' );

        infos := oClient.GetMailInfos();
        UBound := VarArrayHighBound( infos, 1 );
        Count := UBound+1;
        ShowMessage(Format('Total %d email(s)', [Count]));

        for i := 0 to UBound do
        begin
            oInfo := IDispatch(VarArrayGet(infos, i)) as IMailInfo ;
            ShowMessage(Format('Index: %d; Size: %d; UIDL: ' + oInfo.UIDL,
            [oInfo.Index, oInfo.Size]));

            // Generate a random file name by current local datetime,
            // You can use your method to generate the filename if you do not like it
            fileName := mailFolder + '\' + oTools.GenFileName(i) + '.eml';

            // Receive email from Gmail IMAP4 server
            oMail := oClient.GetMail( oInfo );

            ShowMessage( 'From: ' + oMail.From.Address + #13#10 +
                'Subject: ' + oMail.Subject );

            // Save email to local disk
            oMail.SaveAs( fileName, true );

            // Mark email as deleted from Gmail IMAP4 server
            oClient.Delete(oInfo);
        end;

        // Quit and purge emails marked as deleted from Gmail IMAP4 server
        oClient.Quit;

    except
        on ep:Exception do
        ShowMessage( 'Error: ' + ep.Message );
    end;
end;

end.

Gmail IMAP OAUTH

The Gmail IMAP and SMTP servers have been extended to support authorization via the industry-standard OAuth 2.0 protocol. Using OAUTH protocol, user can do authentication by Gmail Web OAuth instead of inputting user and password directly in application. This way is more secure, but a little bit complex.

Using Gmail IMAP OAUTH

Next Section

At next section I will introduce how to download emails from Yahoo account.

Appendix

Comments

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