asp.net 服务器端对话框实现

【核心代码】

using System;
using System.Text;
using System.Web.UI;
using System.ComponentModel;
using System.Collections.Specialized;
using System.Web.UI.Design;
using System.Resources;

using jjstar.AspNetWebControl.Design;

namespace jjstar.AspNetWebControl
{
	[Designer(typeof(WebControlDesigner))]
	public class WebConfirm : System.Web.UI.WebControls.TextBox // System.Web.UI.Control, System.Web.UI.IPostBackEventHandler
	{
		private bool blDoConfirm;
		public event EventHandler ConfirmOK;
		public event EventHandler ConfirmCancel;

		private bool DoConfirm
		{
			get{return blDoConfirm;}
			set{blDoConfirm = value;}
		}
		[Category("行为"),Description("对话框上的确认提示信息。")]
		public string ConfirmMessage
		{
			get
			{
				object obj=ViewState["Msg"];
				return ((null ==obj ) ? null : (string)obj);
			}
			set{ViewState["Msg"] = value;}
		}
		[Browsable(false)]
		public override bool Visible
		{
			get{return false;}
		}
		protected override void Render(HtmlTextWriter output) 
		{
			base.Render(output);
			output.Write("<br>");
		}

		protected override void OnPreRender(EventArgs e)
		{
			if (true==blDoConfirm)
			{
				if((null==ConfirmOK)&&(null==ConfirmCancel)){}
				else
				{
					Page.GetPostBackEventReference(this);
					StringBuilder sbScript=new StringBuilder();
					sbScript.Append("<script language='javascript'>")
						.Append("var " this.ID "flag=confirm('" ConfirmMessage "');");
					if(null!=ConfirmOK)
					{
						sbScript.Append("if(true==" this.ID "flag)")
							.Append(Page.GetPostBackEventReference(this,"ok") ";");
					}
					if(null!=ConfirmCancel)
					{
						sbScript.Append("if(false==" this.ID "flag)")
							.Append(Page.GetPostBackEventReference(this,"cancel") ";");

					}
					sbScript.Append("</script>");
					Page.RegisterStartupScript(this.UniqueID "Confirm",sbScript.ToString());
				}	
			}
			base.OnPreRender(e);
		}      
		public virtual void ShowConfirm()
		{
			DoConfirm=true;
		}
		public virtual void ShowConfirm(string confirmMessage)
		{
			ConfirmMessage=confirmMessage;
			ShowConfirm();
		}
		private bool LoadPostData(string postDataKey,NameValueCollection postData)
		{
			string PostedValue=postData[postDataKey];
			string val=ConfirmMessage;
			if(null==PostedValue||val!=PostedValue)
			{
				ConfirmMessage=PostedValue;
				return true;
			}
			return false;
		}
		public void RaisePostBackEvent(string eventArgument)
		{
			if(eventArgument.ToUpper()=="OK")
				OnConfirmOK();
			if(eventArgument.ToUpper()=="CANCEL")
				OnConfirmCancel();
		}
		protected void OnConfirmOK()
		{
			if(null!=ConfirmOK)
				ConfirmOK(this,new EventArgs());
		}
		
		protected void OnConfirmCancel()
		{
			if(null!=ConfirmCancel)
				ConfirmCancel(this,new EventArgs());
		}

	}

}