.net 控件生命周期

浏览数：33 / 时间：2015年06月09日

这里列举出来了11个生命周期，一般的控件生命周期会经历这11个生命周期，但是有一些特别的控件比如页面控件System.Web.UI.Page等。

具体代码参考如下：

 　　　　/// <summary>
        /// 1. 初始化
        /// </summary>
        /// <param name="e"></param>
        protected override void OnInit(EventArgs e)
        {
            OutPut("1. OnInit");
            base.OnInit(e);
            this.Page.RegisterRequiresPostBack(this);
        }

        /// <summary>
        /// 2. 装载视图
        /// </summary>
        /// <param name="savedState"></param>
        protected override void LoadViewState(object savedState)
        {
            OutPut("2. LoadViewState");
            base.LoadViewState(savedState);
        }

        /// <summary>
        /// 3. 回传数据处理
        /// </summary>
        /// <param name="postDataKey"></param>
        /// <param name="postCollection"></param>
        /// <returns></returns>
        public virtual bool LoadPostData(string postDataKey, NameValueCollection postCollection)
        {
            OutPut("3. LoadPostData");
            return true;
        }

        /// <summary>
        /// 4. 装载时间
        /// </summary>
        /// <param name="e"></param>
        protected override void OnLoad(EventArgs e)
        {
            OutPut("4. OnLoad");
            base.OnLoad(e);
        }

        /// <summary>
        /// 5. 回传事件通知
        /// </summary>
        public virtual void RaisePostDataChangedEvent()
        {
            OutPut("5. RaisePostDataChangedEvent");
        }

        /// <summary>
        /// 6. 处理回发事件
        /// </summary>
        /// <param name="eventArgument"></param>
        public virtual void RaisePostBackEvent(string eventArgument)
        {
            OutPut("6. RaisePostBackEvent");
        }

        /// <summary>
        /// 7. 预呈现
        /// </summary>
        /// <param name="e"></param>
        protected override void OnPreRender(EventArgs e)
        {
            OutPut("7. OnPreRender");
            base.OnPreRender(e);
        }

        /// <summary>
        /// 8 保存视图状态
        /// </summary>
        /// <returns></returns>
        protected override object SaveViewState()
        {
            OutPut("8. SaveViewState");
            base.SaveViewState();
            return new Pair();
        }

        /// <summary>
        /// 9. 呈现 
        /// </summary>
        /// <param name="writer"></param>
        protected override void Render(HtmlTextWriter writer)
        {
            writer.Write("<input type=‘button‘ name=\"{0}\" value=\"Click Me!\" style=‘position: absolute; left: 20px; top: 280px;‘ onclick=\"{1}\" />", "[控件声明周期]", Page.ClientScript.GetPostBackEventReference(this, ""));
            OutPut("9. Render");
            base.Render(writer);

        }

        /// <summary>
        /// 10. 卸载
        /// </summary>
        /// <param name="e"></param>
        protected override void OnUnload(EventArgs e)
        {
            OutPut("10. OnUnload");
            base.OnUnload(e);
        }

        /// <summary>
        /// 11. 释放资源
        /// </summary>
        public override void Dispose()
        {
            OutPut("11. Dispose");
            base.Dispose();
        }

        private void OutPut(string strText)
        {
            if (this.DesignMode == false)
            {
                HttpContext.Current.Response.Write(strText + "<br />");
            }
        }


        [Bindable(true)]
        [Category("Appearance")]
        [DefaultValue("")]
        [Localizable(true)]
        public string Text
        {
            get
            {
                String s = (String)ViewState["Text"];
                return ((s == null) ? String.Empty : s);
            }

            set
            {
                ViewState["Text"] = value;
            }
        }

        protected override void RenderContents(HtmlTextWriter output)
        {
            output.Write(Text);
        }