C#使用System.Net.Mail類實現郵件發(fā)送

第C#使用System.Net.Mail類實現郵件發(fā)送有些SMTP服務器要求在代表客戶端發(fā)送電子郵件前驗證客戶端的身份。當此SmtpClient對象應該使用當前登錄用戶的默認憑據進行身份驗證（如果服務器要求）時，請將此屬性設置為true。對于客戶端應用程序，這是在大多數情況下都需要的行為。也可以使用應用程序和計算機配置文件指定憑據信息。有關更多信息，請參見mailSettings元素（網絡設置）。

如果UseDefaultCredentials屬性設置為false，則連接到服務器時會將Credentials屬性中設置的值用作憑據。如果UseDefaultCredentials屬性設置為false并且尚未設置Credentials屬性，則將郵件以匿名方式發(fā)送到服務器。UseDefaultCredentials的默認值為false。

如果提供用于基本身份驗證的憑據，則憑據將以明文形式發(fā)送到服務器。這可能會產生安全問題，因為憑據可以被他人看見從而加以利用。但是向163的郵箱發(fā)送郵件是必須要帶上發(fā)送者的憑據信息，否則郵件是發(fā)送不出去的。

SmtpClient也可以這樣建立:SmtpClientclient=newSmtpClient(smtp_server)，因為郵件發(fā)送服務器的默認端口是25。

1、QQ郵箱向163郵箱發(fā)送郵件

privatestaticvoidTimeEvent(objectsource,ElapsedEventArgse)

stringsmtp_server="";

intport=25;

stringmail_from="***from_mail_username***@";

stringsender="***from_mail_username***";

stringmail_to="***to_mail_username***@163.com";

stringreceiver="***to_mail_username***@";

stringsubject="TitleTest"

stringbody="ContentTest";

SendEmail(smtp_server,port,mail_from,sender,mail_to,receiver,subject,body);

catch(Exceptionex)

MessageBox.Show(ex.Message);

publicstaticvoidSendEmail(stringsmtp_server,intport,stringmail_from,stringsender,stringmail_to,stringreceiver,stringsubject,stringbody)

MailAddressfrom=newMailAddress(mail_from,sender);

MailAddressto=newMailAddress(mail_to,receiver);

MailMessagemessage=newMailMessage(from,to);

message.BodyEncoding=Encoding.UTF8;

message.IsBodyHtml=true;

message.Subject=subject;

message.Body=body;

SmtpClientclient=newSmtpClient(smtp_server,port);

client.Credentials=newNetworkCredential("***from_mail_username***@","***pwd***");

client.Send(message);

}

2、163郵箱向163郵箱發(fā)送郵件

privatestaticvoidTimeEvent(objectsource,ElapsedEventArgse)

stringsmtp_server="";

intport=25;

stringmail_from="***from_mail_username***@163.com";

stringsender="***from_mail_username***";

stringmail_to="***to_mail_username***@163.com";

stringreceiver="***to_mail_username***";

stringsubject="TitleTest"

stringbody="ContentTest";

SendEmail(smtp_server,port,mail_from,sender,mail_to,receiver,subject,body);

catch(Exceptionex)

MessageBox.Show(ex.Message);

publicstaticvoidSendEmail(stringsmtp_server,intport,stringmail_from,stringsender,stringmail_to,stringreceiver,stringsubject,stringbody)

MailAddressfrom=newMailAddress(mail_from,sender);

MailAddressto=newMailAddress(mail_to,receiver);

MailMessagemessage=newMailMessage(from,to);

message.BodyEncoding=Encoding.UTF8;

message.IsBodyHtml=true;

message.Subject=subject;

message.Body=body;

SmtpClientclient=newSmtpClient(smtp_server);

client.Credentials=newNetworkCredential("***from_mail_username***@163.com","***pwd***");

client.Send(message);

}

3、163郵箱向QQ郵箱發(fā)送郵件

privatestaticvoidTimeEvent(objectsource,ElapsedEventArgse)

stringsmtp_server="";

intport=25;

stringmail_from="***from_mail_username***@163.com";

stringsender="***from_mail_username***";

stringmail_to="***to_mail_username***@";

stringreceiver="***to_mail_username***";

stringsubject="TitleTest"

stringbody="ContentTest";

SendEmail(smtp_server,port,mail_from,sender,mail_to,receiver,subject,body);

catch(Exceptionex)

MessageBox.Show(ex.Message);

publicstaticvoidSendEmail(stringsmtp_server,intport,stringmail_from,stringsender,stringmail_to,stringreceiver,stringsubject,stringbody)

MailAddressfrom=newMailAddress(mail_from,sender);

MailAddressto=newMailAddress(mail_to,receiver);

MailMessagemessage=newMailMessage(from,to);

message.BodyEncoding=Encoding.UTF8;

message.IsBodyHtml=true;

message.Subject=subject;

message.Body=body;

SmtpClientclient=newSmtpClient(smtp_server);

client.Credentials=newNetworkCredential("***from_mail_username***@163.com","***pwd***");

client.Send(message);

}

4、QQ郵箱向QQ郵箱發(fā)送郵件

privatestaticvoidTimeEvent(objectsource,ElapsedEventArgse)

stringsmtp_server="";

intport=25;

stringmail_from="***from_mail_username***@";

stringsender="***from_mail_username***";

stringmail_to="***to_mail_username***@";

stringreceiver="***to_mail_username***";

stringsubject="TitleTest"

stringbody="ContentTest";

SendEmail(smtp_server,port,mail_from,sender,mail_to,receiver,subject,body);

catch(Exceptionex)

MessageBox.Show(ex.Message);

publicstaticvoidSendEmail(stringsmtp_server,intport,stringmail_from,stringsender,stringmail_to,stringreceiver,stringsubject,stringbody)

MailAddressfrom=newMailAddress(mail_from,sender);

MailAddressto=newMailAddress(mail_to,receiver);

MailMessagemessage=newMailMessage(from,to);

message.BodyEncoding=Encoding.UTF8;

message.IsBodyHtml=true;

message.Subject=subject;