c# SMTP发送邮件

string from = "";
string fromAlias = "MIS-TC";
string[] to = { "" };
string subject = "问题提交";
string body = sb.ToString();
string ipaddr = "smtp.email.qq.com";
int port = 25;
string credit = "";
string password = "";
SqlhelperClass.sqlHelper.SMTP(from, fromAlias, to, subject, body, ipaddr, port, credit, password);

public static void SMTP(string from,string fromAlias, string[] to, string subject, string body, string ipaddr, int port, string creditAccount, string password)
{
    try
    {
        ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12;
        // 创建电子邮件消息对象
        MailMessage message = new MailMessage
        {
            From = new MailAddress(from, fromAlias)
        };
        foreach (string recipient in to)
        {
            message.To.Add(new MailAddress(recipient));
        }

        // 设置邮件主题和正文
        message.Subject = subject;
        message.Body = body;
        message.BodyEncoding = Encoding.UTF8;

        // 创建SMTP客户端
        SmtpClient client = new SmtpClient(ipaddr, port); // SMTP服务器地址和端口
        client.EnableSsl = false; // 如果服务器支持SSL

        如果SMTP服务器需要身份验证
        client.Credentials = new NetworkCredential(creditAccount, password);

        // 发送邮件
        client.Send(message);
        Serilog.Log.Warning("邮件发送成功!");
    }
    catch (Exception ex)
    {
        Serilog.Log.Error(ex.Message);
    }
}