Parameter HTTP 参数基类

namespace ControlLibrary {
    using System;
    using System.Data;
    using System.Configuration;
    using System.Web;
    using System.Web.Security;
    using System.Web.UI;
    using System.Web.UI.WebControls;
    using System.Web.UI.WebControls.WebParts;
    using System.Web.UI.HtmlControls;


    public class PagePropertyParameter : Parameter {

        private String _key;

        public String Key {
            get {
                return _key;
            }
            set {
                _key = value;
            }
        }

        protected override object Evaluate(HttpContext context, Control control) {
            Type t = control.Page.GetType();
            System.Reflection.PropertyInfo pi = t.GetProperty(Key, System.Reflection.BindingFlags.Instance | System.Reflection.BindingFlags.Public | System.Reflection.BindingFlags.NonPublic);
            return pi.GetValue(control.Page, null);
        }
    }

    public class ViewStateParameter : Parameter {

        private String _key;

        public String Key {
            get {
                return _key;
            }
            set {
                _key = value;
            }
        }

        protected override object Evaluate(HttpContext context, Control control) {
            Type t = control.Page.GetType();
            System.Reflection.PropertyInfo pi = t.GetProperty("ViewState", System.Reflection.BindingFlags.Instance | System.Reflection.BindingFlags.NonPublic);
            StateBag pageViewState = pi.GetValue(control.Page, null) as StateBag;
            return pageViewState[Key];
        }
    }

    public class RequestParameter : Parameter
    {
        private String _key;

        public String Key
        {
            get
            {
                return _key;
            }
            set
            {
                _key = value;
            }
        }

        protected override object Evaluate(HttpContext context, Control control)
        {
            return context.Request.Params.Get(_key);
           // return base.Evaluate(context, control);
        }
    }
}2.使用方法

  <asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString="<%$ ConnectionStrings:pubsConnectionString1 %>"
            ProviderName="<%$ ConnectionStrings:pubsConnectionString1.ProviderName %>" SelectCommand="SELECT [stor_id], [stor_name], [stor_address], [city], [state], [zip] FROM [stores] WHERE ([stor_name] LIKE '%' + @stor_name + '%')">
            <SelectParameters>
                <%--<cc1:ViewStateParameter Name="stor_name" Key="TestState" Type="String" />--%>
               <%-- <cc1:PagePropertyParameter Name="stor_name" Key="TestValue" Type="String" />--%>
                <cc1:RequestParameter Name="stor_name" Key="Name" Type="String" />
            </SelectParameters>
        </asp:SqlDataSource>

代码来源：http://www.cnblogs.com/CSharp/