找不到类型或命名空间名称

找不到类型或命名空间名称“Yym_sql”(是否缺少 using 指令或程序集引用?)

using System;
using System.Data;
using System.Configuration;
using System.Collections;
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;
using System.Data.OleDb;
public partial class Admin_Yym_Product_AdminPPai : System.Web.UI.Page
{
    Yym_sql Exsql = new Yym_sql();
    protected void Page_Load(object sender, EventArgs e)
    {  
        if(!IsPostBack){
            switch (Request["Yym_FS"])
            {
                case "Add":
                    this.Panel1.Visible = false;
                    this.Panel2.Visible = true;
                 
                    break;    
                case "Del":
                    del();
                    break;
                default:
                    this.Panel1.Visible = true;
                    this.Panel2.Visible = false;
                  
                    bind();
                    break;
            }
        }    }
    void AddPp(string Name1) {
        if (Request.Form["classroot"] == "0") {
            ChangeHope_fc.Show_Msg("请选择分类");
            Response.End();
        }
        Exsql.Open();
        string sql = "insert into Yym_PinPai (Yym_PinPaiName,Yym_ClassID) values (@Yym_PinPaiName,@Yym_ClassID)";
        OleDbCommand com = new OleDbCommand(sql,Exsql.con);
        com.Parameters.Add(new OleDbParameter("@Yym_PinPaiName", OleDbType.VarChar, 50));
        com.Parameters[0].Value = Name1;
        com.Parameters.Add(new OleDbParameter("@Yym_Yym_ClassID", OleDbType.SmallInt));
        com.Parameters[1].Value = Convert.ToInt16(Request.Form["classroot"]);
        com.ExecuteNonQuery();
        Exsql.Close();
    
    }
    protected void Button1_Click(object sender, EventArgs e)
    {
        AddPp(this.Yym_pp.Text);
        ChangeHope_fc.Show_Msg("操作成功！","AdminPPai.aspx?Yym_FS=Add");
    }
   
    void del() {
        try
        {
            Exsql.Open();
            string sql = "delete from Yym_PinPai where Yym_ID=" + Convert.ToInt16(Request["Yym_MID"]);
            OleDbCommand com = new OleDbCommand(sql, Exsql.con);
            com.ExecuteNonQuery();
            Exsql.Close();
        }
        finally
        {
            ChangeHope_fc.Show_Msg("操作成功！", "AdminPPai.aspx?Yym_FS=admin");
        }
       
    
    
    }
    private PagedDataSource datalistbind(DataSet dst)
    {        PagedDataSource objpage = new PagedDataSource();
        objpage.DataSource = dst.Tables[0].DefaultView;
        objpage.AllowPaging = true;
        //dg1.PageSize = 20;
        objpage.PageSize = 20;
        int CurPage;
        //判断是否有分页的请求；        ///
        if (Request["iPage"] != null)
        {
            CurPage = Convert.ToInt32(Request["iPage"]);
        }
        else
        {
            CurPage = 1;
        }
        //设置当前页；
        objpage.CurrentPageIndex = CurPage - 1;
        Label1.Text = "当前页：第" + CurPage.ToString() + "/" + objpage.PageCount + "页";
        Label2.Text = "共有" + objpage.DataSourceCount + "条记录　" + objpage.PageSize + "/页";
        //判断不是第一页的时候
        if (!objpage.IsFirstPage)
        {            this.prev.NavigateUrl = Request.CurrentExecutionFilePath + "?iPage=" + (Convert.ToInt32(CurPage) - 1);
        }
        this.start.NavigateUrl = Request.CurrentExecutionFilePath + "?iPage=1";
        //判断不是最后一页的时候
        if (!objpage.IsLastPage)
        {
            this.next.NavigateUrl = Request.CurrentExecutionFilePath + "?ipage=" + (Convert.ToInt32(CurPage) + 1);
        }
        this.max.NavigateUrl = Request.CurrentExecutionFilePath + "?iPage=" + objpage.PageCount;
        if (!IsPostBack)
        {
            for (int i = 1; i < objpage.PageCount + 1; i++)
            {
                this.iPage.Items.Add(new ListItem(i.ToString() + "页", i.ToString()));
            }
        }        return objpage;
    }
    protected void sic(object sender, EventArgs e)
    {
        string sql = "select * from Yym_PinPai";
        ChangHope_DB Chp = new ChangHope_DB();
        DataSet ds = Chp.Db_ds(sql, "loginfo");
        PagedDataSource objpage = new PagedDataSource();
        objpage.DataSource = ds.Tables[0].DefaultView;
        objpage.AllowPaging = true;
        //dg1.PageSize = 20;
        objpage.PageSize = 20;
        int CurPage;
        //判断是否有分页的请求；        ///
        if (iPage.SelectedValue != null)
        {
            CurPage = Convert.ToInt32(iPage.SelectedValue);
        }
        else
        {
            CurPage = 1;
        }
        //设置当前页；
        objpage.CurrentPageIndex = CurPage - 1;
        Label1.Text = "当前页：第" + CurPage.ToString() + "/" + objpage.PageCount + "页";
        Label2.Text = "共有" + objpage.DataSourceCount + "条记录　" + objpage.PageSize + "/页";
        //判断不是第一页的时候
        if (!objpage.IsFirstPage)
        {            this.prev.NavigateUrl = Request.CurrentExecutionFilePath + "?iPage=" + (Convert.ToInt32(CurPage) - 1);
        }
        this.start.NavigateUrl = Request.CurrentExecutionFilePath + "?iPage=1";
        //判断不是最后一页的时候
        if (!objpage.IsLastPage)
        {
            this.next.NavigateUrl = Request.CurrentExecutionFilePath + "?ipage=" + (Convert.ToInt32(CurPage) + 1);
        }
        this.max.NavigateUrl = Request.CurrentExecutionFilePath + "?iPage=" + objpage.PageCount;
        if (!IsPostBack)
        {
            for (int i = 1; i < objpage.PageCount + 1; i++)
            {
                this.iPage.Items.Add(new ListItem(i.ToString() + "页", i.ToString()));
            }
        }
        this.dg1.DataSource = objpage; //ds.Tables["dstable"].DefaultView;
        this.dg1.DataBind();    }
    private void bind()
    {
        try
        {            Exsql.Open();
            string sql = "select * from Yym_PinPai";
            ChangHope_DB Chp = new ChangHope_DB();
            DataSet ds = Chp.Db_ds(sql, "Yym_PinPai");
            this.dg1.DataSource = datalistbind(ds);
            this.dg1.DataBind();
        }
        catch (Exception ee)
        {            Response.Write(ee.Message);
        }
        finally
        {            Exsql.Close();        }    }
   
    protected void Button2_Click(object sender, EventArgs e)
    {    }
    public string RetParent_Name(int ClassID)
    {
        Exsql.Open();
        string r}
etname = "";
        string sql = "Select Yym_ClassName from Yym_ProductClass where Yym_ID=" + ClassID;
        OleDbCommand com = new OleDbCommand(sql, Exsql.con);
        OleDbDataReader dr = com.ExecuteReader(CommandBehavior.CloseConnection);
        if (dr.Read())
        {
            retname = dr[0].ToString();
        }
        dr.Close();
        Exsql.Close();
        return retname;
    }