学习打造自己的AJAX控件！

    开始学习打造属于自己的AJAX控件！本文先打造一个简单的文本框控件，实现当鼠标移上文本框时，文本框高亮显示。
以后再扩展其他功能，如正则表达式的验证，输入匹配等功能！那就开始吧！
    首先我们建一个类库命名为Ajax.MyControls,然后新建一个类文件，我们命名为MyTextBox,再建立一个MyTextBox.js并将其文件嵌入资源.
    接着开始我们的打造之路。打开MyTextBox类，
引入下列命名空间。

using System;
using System.Collections.Generic;
using System.Text;
using System.Web;
using System.Web.UI;
using System.Security.Permissions;
using System.ComponentModel;
using System.Diagnostics;
using System.Web.UI.WebControls;

设置其继承Control,IScriptControl接口。
不好意思，来到这里我插入不了代码，点那按钮N久没出来，只能这样帖出来了，看起来比较痛苦！没办法！

[assembly: WebResource("Ajax.MyControls.MyTextBox.js", "text/javascript")]
namespace Ajax.MyControls
{
    [AspNetHostingPermission(SecurityAction.Demand, Level = AspNetHostingPermissionLevel.Minimal)]
    [AspNetHostingPermission(SecurityAction.InheritanceDemand, Level = AspNetHostingPermissionLevel.Minimal)]
    [ToolboxData("<{0}:MyTextBox runat=\"server\"></{0}:MyTextBox>")]
    public class MyTextBox:Control,IScriptControl
    {
       
        public MyTextBox()
        {
        }
    }

}

Control,IScriptControl

下面开始定义改控件的属性
  #region 所有属性
        [Category("样式")]
        [DefaultValue("textbox")]
        [Description("控件的样式")]
        public string CssClass
        {
            [DebuggerStepThrough()]
            get
            {
                object obj = ViewState["cssClass"];
                return (obj == null) ? "textbox" : (string)obj;
            }
            [DebuggerStepThrough()]
            set
            {
                ViewState["cssClass"] = value;
            }
        }

        [Category("样式")]
        [DefaultValue("textbox")]
        [Description("控件高亮时的样式")]
        public string HighLightCssClass
        {
            [DebuggerStepThrough()]
            get
            {
                object obj = ViewState["HighLightCssClass"];
                return (obj == null) ? "HighLight" : (string)obj;
            }
            [DebuggerStepThrough()]
            set
            {
                ViewState["HighLightCssClass"] = value;
            }
        }

        [Category("高级")]
        [DefaultValue("")]
        [Description("控件的文本值")]
        public string Text
        {
            [DebuggerStepThrough()]
            get
            {
                object obj = ViewState["Text"];
                return (obj == null) ? string.Empty : (string)obj;
            }
            [DebuggerStepThrough()]
            set
            {
                ViewState["Text"] = value;
            }
        }

      
      
        #endregion

下面重写方法
  [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Security", "CA2109:ReviewVisibleEventHandlers")]
        protected override void OnPreRender(EventArgs e)
        {
            base.OnPreRender(e);

            ScriptManager scriptManager = ScriptManager.GetCurrent(this.Page);
            if (scriptManager == null)
            {
                throw new InvalidOperationException("页面必须存在一个ScriptManager控件.");
            }
            scriptManager.RegisterScriptControl(this);
        }
        

        protected override void Render(HtmlTextWriter writer)
        {
          
            writer.AddAttribute(HtmlTextWriterAttribute.Id, this.ClientID);                    

          
            if (!string.IsNullOrEmpty(this.Text))
            {
                writer.AddAttribute(HtmlTextWriterAttribute.Value, this.Text);
            }
          
            writer.AddAttribute(HtmlTextWriterAttribute.Type, "text");
      if (!string.IsNullOrEmpty(this.HighLightCssClass))
            {
                 writer.AddAttribute("onfocus", "this.className ='" + this.HighLightCssClass + "'; ");
            } //在这里我们设置获取鼠标事件时显示高亮的样式
         
            if (!string.IsNullOrEmpty(this.CssClass))
            {
                writer.AddAttribute("onblur", "this.className = '" + this.CssClass + "'; ");
            }//在这里我们设置失去鼠标事件时显示原来的样式
            writer.RenderBeginTag(HtmlTextWriterTag.Input);
            writer.RenderEndTag();               
          

            if (!this.DesignMode)
            {
                ScriptManager.GetCurrent(this.Page).RegisterScriptDescriptors(this);
            }
        }
                  
        public IEnumerable<ScriptDescriptor> GetScriptDescriptors()
        {
            ScriptControlDescriptor desc = new ScriptControlDescriptor(this.GetType().FullName, this.ClientID);

          

            if (!string.IsNullOrEmpty(Text))
            {
                desc.AddProperty("Text", Text);
            }
                                        

            yield return desc;
        }

        public IEnumerable<ScriptReference> GetScriptReferences()//这里记得发布脚本资源
        {
            yield return new ScriptReference(this.Page.ClientScript.GetWebResourceUrl(this.GetType(), "Ajax.MyControls.MyTextBox.js"));
        }

基本上这个类就完成了！
开始JS的编写。

Type.registerNamespace('Ajax.MyControls');

Ajax.MyControls.CuteTextBox = function(element)
{
    this._cssClass = '';
    this._Text = '';
    this._HighLightCssClass='';
  
    Ajax.MyControls.MyTextBox.initializeBase(this, [element]);
}

声明属性

Ajax.MyControls.prototype=
{
    get_cssClass : function()
    {
         if (arguments.length !== 0) throw Error.parameterCount();

        return this._cssClass;
    },
   
    set_cssClass : function(value)
    {
        var e = Function._validateParams(arguments, [{name: 'value', type: String}]);
        if (e) throw e;

        if (this._cssClass != value)
        {
            this._cssClass = value;
            this.raisePropertyChanged('cssClass');

            var target = this.get_element();

            if (!Sys.UI.DomElement.containsCssClass(target, value))
            {
                Sys.UI.DomElement.addCssClass(target, value);
            }
        }
    },

。。。。。。。。。。。。下面的这些属性就不写了，都是一样的，无非就是get,set
}
到了后面别忘了注册咯。

Ajax.MyControls.MyTextBox.registerClass('Ajax.MyControls.MyTextBox', Sys.UI.Control);

if (typeof(Sys) != 'undefined')
{
    Sys.Application.notifyScriptLoaded();
}

来到这里基本上就差不多了！一些细节，自己调了！