C# 自定义控件OnButton单击重写C的事件处理程序#

我有一个发送电子邮件的复合自定义控件。单击按钮即可发送邮件。但是，邮件是在我点击两次按钮后发送的。有人知道为什么会这样吗？我该如何解决？代码如下：

namespace EmailControl
{
    [DefaultProperty("Text")]
    [ToolboxData("<{0}:ServerControl1 runat=server></{0}:ServerControl1>")]
    public class ServerControl1 : WebControl,INamingContainer
    {
        public string Text
        {
            get { return ViewState["Text"] as string ?? "[" + this.ID + "]"; }
            set { ViewState["Text"] = value; }
        }

        public string Host
        {
            get { return ViewState["host"] as string ?? "[" + this.ID + "]"; }
            set { ViewState["host"] = value; }
        }

        public string From
        {
            get { return ViewState["from"] as string ?? "[" + this.ID + "]"; }
            set { ViewState["from"] = value; }
        }

        public int Port
        {
            get { return (int) ViewState["port"]; }
            set { ViewState["port"] = value; }
        }

        public string UserName
        {
            get { return ViewState["user"] as string ?? "[" + this.ID + "]"; }
            set { ViewState["user"] = value; }
        }

        public string Password
        {
            get { return ViewState["pass"] as string ?? "[" + this.ID + "]"; }
            set { ViewState["pass"] = value; }
        }

        TextBox txtEmail;
        TextBox txtBody;
        TextBox txtSubject;
        Button btnSend;

        protected override void CreateChildControls()
        {
            txtEmail = new TextBox();
            txtEmail.ID = "txtEmail";
            txtEmail.AutoPostBack = true;
            LiteralControl l1 = new LiteralControl("<br/>");
            txtSubject = new TextBox();
            txtSubject.ID = "txtSubject";
            txtEmail.AutoPostBack = true;
            this.Controls.Add(txtEmail);
            this.Controls.Add(txtSubject);
            LiteralControl l2= new LiteralControl("<br/>");
            txtBody = new TextBox();
            txtBody.ID = "txtBody";
            txtBody.AutoPostBack = true;
            txtBody.TextMode = TextBoxMode.MultiLine;
            txtBody.Width = 200;
            txtBody.Height = 200;
            this.Controls.Add(txtBody);
            btnSend = new Button();
            btnSend.ID = "btnSend";
            btnSend.Width = 100;
            btnSend.Text = "Send";
            btnSend.Click += new EventHandler(OnButtonClick);
            this.Controls.Add(btnSend);
        }

        protected void OnButtonClick(object sender,EventArgs e)
        {
            TextBox txtEmail = (TextBox)this.FindControl("txtEmail");
            MailMessage msg = new MailMessage(From,txtEmail.Text);
            TextBox txtSubject = (TextBox)this.FindControl("txtSubject");
            TextBox txtBody = (TextBox)this.FindControl("txtBody");
            msg.Subject = txtSubject.Text;
            msg.Body = txtBody.Text;

            SmtpClient smtp = new SmtpClient();
            smtp.Host = Host;
            smtp.Port = Convert.ToInt32(Port);
            smtp.EnableSsl = true;
            smtp.Credentials = new System.Net.NetworkCredential(UserName,
                Password);
            smtp.Send(msg);
        }
    }
}

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你是说每次点击按钮都会发送电子邮件？如果是这样，您只需要防止第二次回发。请看这里：

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为了吸引更多的答案，您应该添加一个与您使用的语言或工具相对应的标签。您可以通过在编辑页面的底部添加标签来完成此操作。是否尝试调试它？您的事件是被触发两次还是其他什么？