Asp.net技术点GridView+AspnetPager+Linq+ViewState 处理数据条件问题

今天第一次发布文章解决

查询条件保存：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

public partial class UserManager : System.Web.UI.Page
{

    //调用获取 数据方法
    MapUni.BLL.BLL.Test_tblSalesPerson bll = new MapUni.BLL.BLL.Test_tblSalesPerson();

    //定义ViewState的key值
    const string vsKey = "searchCriteria";

    ///<summary>
    /// 界面初始化
    ///</summary>
    ///<param name="sender"></param>
    ///<param name="e"></param>
    protected void Page_Load(object sender, EventArgs e)
    {     
        if (!IsPostBack) 
        {
            //界面初始化绑定数据
            Bind_Grid(string.Empty);
        }
    }

    ///<summary>
    /// 绑定数据
    ///</summary>
    ///<param name="str_where"></param>
    public void Bind_Grid(string str_where)
    {
        //进行数据 判断 
        if (str_where == null)
        {
            str_where = "";
        }
        //获取list数据
        var Test_DataList = bll.GetModelList(str_where);

        //设置分页控件的记录总数
        AspNetPager1.RecordCount = Test_DataList.Count();

        //linq处理数据数显示
        var qureys =( from m in Test_DataList select m).Skip(AspNetPager1.StartRecordIndex-1).Take(AspNetPager1.PageSize);

        //数据绑定
        this.GridView1.DataSource = qureys;
        this.GridView1.DataBind();
    }

    ///<summary>
    /// 点击查询方法
    ///</summary>
    ///<param name="sender"></param>
    ///<param name="e"></param>
    protected void btnSelect_Click(object sender, EventArgs e)
    {

　　　　　　//设置查询为第一页显示
            AspNetPager1.CurrentPageIndex = 1;

        //判断用户名是否为空
        if (this.txt_UserName.Text.Length != 0)
        {

            //带入查询条件
            string where = " UserName like '%" + this.txt_UserName.Text + "%'";

            //保存条件到ViewState
            ViewState[vsKey] = where;
            //进行数据绑定
            Bind_Grid(where);
        }
        else 
        {
            ViewState[vsKey] = null;
            //进行数据绑定
            Bind_Grid(string.Empty);
         
        }
    }


    ///<summary>
    /// 点击翻页控件查询
    ///</summary>
    ///<param name="sender"></param>
    ///<param name="e"></param>

    protected void AspNetPager1_PageChanged1(object sender, EventArgs e)
    {
        //获取查询条件
        Bind_Grid((string)ViewState[vsKey]);
    }
}