GridView结合dropdownlist更改父级ID

时间 2020-09-21 标签 gridview 结合 dropdownlist 更改

PS：带有注释部分的内容为实现的关键html

  
  
  
  
   
   
   
   <%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default2.aspx.cs" Inherits="Default2" %> 
   
   
   
    
   
   
   
   <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 
   
   
   
    
   
   
   
   <html xmlns="http://www.w3.org/1999/xhtml"> 
   
   
   
   <head runat="server"> 
   
   
   
       <title></title> 
   
   
   
   </head> 
   
   
   
   <body> 
   
   
   
       <form id="form1" runat="server"> 
   
   
   
       <div> 
   
   
   
           <asp:GridView ID="gvStudent2" runat="server"  AutoGenerateColumns="False"   
   
   
   
               CellPadding="4" ForeColor="#333333" GridLines="None"   
   
   
   
               onrowcancelingedit="gvStudent2_RowCancelingEdit"   
   
   
   
               onrowdatabound="gvStudent2_RowDataBound" onrowdeleting="gvStudent2_RowDeleting"   
   
   
   
               onrowediting="gvStudent2_RowEditing" onrowupdating="gvStudent2_RowUpdating"   
   
   
   
               onselectedindexchanging="gvStudent2_SelectedIndexChanging"   
   
   
   
               onpageindexchanging="gvStudent2_PageIndexChanging" DataKeyNames="id"> 
   
   
   
               <RowStyle BackColor="#EFF3FB" /> 
   
   
   
             
   
   
   
        <Columns> 
   
   
   
       <asp:BoundField HeaderText="编号" Visible="false"  DataField="id"/>   
   
   
   
            
   
   
   
           <asp:TemplateField HeaderText ="姓名"> 
   
   
   
           <ItemTemplate> 
   
   
   
            <%#Eval("name")%> 
   
   
   
           </ItemTemplate> 
   
   
   
           <EditItemTemplate> 
   
   
   
            <asp:textbox ID ="TBName" Text='<%#Eval("name") %>' runat="server">'> 
   
   
   
            </asp:textbox> 
   
   
   
           </EditItemTemplate> 
   
   
   
           </asp:TemplateField>         
   
   
   
         
   
   
   
              
   
   
   
           <asp:TemplateField HeaderText ="父级" > 
   
   
   
           <ItemTemplate> 
   
   
   
               <%#Eval("PName") %> 
   
   
   
           </ItemTemplate> 
   
   
   
           <EditItemTemplate> 
   
   
   
              <asp:HiddenField ID="HDFParentStu" runat="server" Value='<%# Eval("PId") %>' /><%--存储实际要操做的字段 --%> 
   
   
   
              <asp:DropDownList ID="DDLParentStu" runat="server" Width="90px" /> 
   
   
   
           </EditItemTemplate>          
   
   
   
           </asp:TemplateField>       
   
   
   
              
   
   
   
            <asp:CommandField ShowEditButton="True" /> 
   
   
   
            <asp:CommandField ShowDeleteButton="True" /> 
   
   
   
              
   
   
   
           </Columns>        
   
   
   
                 <PagerSettings FirstPageText="" LastPageText="" NextPageText="" PreviousPageText="" /> 
   
   
   
                               <RowStyle Height="20px" BackColor="#F7F6F3" ForeColor="#333333" /> 
   
   
   
                               <FooterStyle BackColor="#5D7B9D" Font-Bold="True" ForeColor="White" /> 
   
   
   
                               <EditRowStyle BackColor="#999999" /> 
   
   
   
                               <SelectedRowStyle BackColor="#E2DED6" Font-Bold="True" ForeColor="#333333" /> 
   
   
   
                               <PagerStyle BackColor="#284775" ForeColor="White" HorizontalAlign="Center" /> 
   
   
   
                               <HeaderStyle BackColor="#5D7B9D" Font-Bold="True" ForeColor="White" /> 
   
   
   
                               <AlternatingRowStyle BackColor="White" ForeColor="#284775" />            
   
   
   
           </asp:GridView> 
   
   
   
      
   
   
   
       </div> 
   
   
   
       </form> 
   
   
   
   </body> 
   
   
   
   </html>

C#代码web

  
  
  
  
   
   
   
   using System;  
   
   
   
   using System.Collections.Generic;  
   
   
   
   using System.Linq;  
   
   
   
   using System.Web;  
   
   
   
   using System.Web.UI;  
   
   
   
   using System.Web.UI.WebControls;  
   
   
   
   using System.Configuration;  
   
   
   
   using System.Data;  
   
   
   
   using System.Data.SqlClient;  
   
   
   
   using System.Collections;  
   
   
   
    
   
   
   
   public partial class Default2 : System.Web.UI.Page  
   
   
   
   {  
   
   
   
       protected void Page_Load(object sender, EventArgs e)  
   
   
   
       {  
   
   
   
           if (!IsPostBack)//首次加载和访问，ispostback=true 表示为相应客户端回发而加载  
   
   
   
               GridViewBind();       
   
   
   
       }  
   
   
   
    
   
   
   
       protected void gvStudent2_PageIndexChanging(object sender, GridViewPageEventArgs e)  
   
   
   
       {  
   
   
   
           gvStudent2.PageIndex = e.NewPageIndex;//当前显示页的索引  
   
   
   
           GridViewBind();  
   
   
   
       }  
   
   
   
       protected void gvStudent2_RowCancelingEdit(object sender, GridViewCancelEditEventArgs e)  
   
   
   
       {  
   
   
   
           gvStudent2.EditIndex = -1;  
   
   
   
           GridViewBind();  
   
   
   
       }  
   
   
   
       protected void gvStudent2_RowDataBound(object sender, GridViewRowEventArgs e)  
   
   
   
       {  
   
   
   
           string StrConn = ConfigurationManager.ConnectionStrings["MyConnectionString"].ConnectionString.ToString();  
   
   
   
          //绑定dropdownlist 的值  
   
   
   
           if (((DropDownList)e.Row.FindControl("DDLParentStu")) != null)  
   
   
   
           {  
   
   
   
               DropDownList DDLParentStu = (DropDownList)e.Row.FindControl("DDLParentStu");  
   
   
   
    
   
   
   
               string sqlStr = "select id as Pid,name as PName from Category"; //取本表中的 id 、name 做为父ID、父name的集合  
   
   
   
               DataSet ds = new DataSet();  
   
   
   
               SqlConnection conn = new SqlConnection(StrConn);  
   
   
   
    
   
   
   
               conn.Open();  
   
   
   
               SqlDataAdapter da = new SqlDataAdapter(sqlStr, conn);  
   
   
   
               da.Fill(ds);  
   
   
   
               conn.Close();              
   
   
   
    
   
   
   
               DDLParentStu.DataSource = ds.Tables[0].DefaultView;//从库中获取数据  
   
   
   
               DDLParentStu.DataTextField = "PName";//列表项提供文本内容的数据源字段 （显示在dropdownlist的可见文本）  
   
   
   
               DDLParentStu.DataValueField = "Pid";//各列表项提供值的数据源字段   （实际要操控的字段）  
   
   
   
               DDLParentStu.DataBind();  
   
   
   
    
   
   
   
               DDLParentStu.SelectedValue = ((HiddenField)e.Row.FindControl("HDFParentStu")).Value; //Pid 与 PName 的完美结合  
   
   
   
           }     
   
   
   
         
   
   
   
            
   
   
   
       }  
   
   
   
       protected void gvStudent2_RowDeleting(object sender, GridViewDeleteEventArgs e)  
   
   
   
       {  
   
   
   
           string StrConn = ConfigurationManager.ConnectionStrings["MyConnectionString"].ConnectionString.ToString();  
   
   
   
    
   
   
   
           string id = gvStudent2.DataKeys[e.RowIndex].Values[0].ToString();  
   
   
   
           string sql = "delete from student where id=" + id;  
   
   
   
    
   
   
   
           try  
   
   
   
           {  
   
   
   
               SqlConnection conn = new SqlConnection(StrConn);  
   
   
   
               if (conn.State.ToString() == "Closed") conn.Open();  
   
   
   
               SqlCommand comm = new SqlCommand(sql, conn);  
   
   
   
               comm.ExecuteNonQuery();  
   
   
   
               comm.Dispose();  
   
   
   
               if (conn.State.ToString() == "Open") conn.Close();  
   
   
   
    
   
   
   
               gvStudent2.EditIndex = -1;  
   
   
   
               GridViewBind();  
   
   
   
           }  
   
   
   
           catch (Exception ex)  
   
   
   
           {  
   
   
   
               Response.Write("数据库错误，错误缘由：" + ex.Message);  
   
   
   
               Response.End();  
   
   
   
           }  
   
   
   
    
   
   
   
       }  
   
   
   
       protected void gvStudent2_RowEditing(object sender, GridViewEditEventArgs e)  
   
   
   
       {  
   
   
   
           gvStudent2.EditIndex = e.NewEditIndex;//所编辑行的索引  
   
   
   
           GridViewBind();  
   
   
   
       }  
   
   
   
       protected void gvStudent2_RowUpdating(object sender, GridViewUpdateEventArgs e)  
   
   
   
       {  
   
   
   
           string StrConn = ConfigurationManager.ConnectionStrings["MyConnectionString"].ConnectionString.ToString();  
   
   
   
           try  
   
   
   
           {  
   
   
   
                      
   
   
   
               string id = ((GridView)sender).DataKeys[e.RowIndex].Values["id"].ToString();  
   
   
   
    
   
   
   
               string name = ((TextBox)gvStudent2.Rows[e.RowIndex].FindControl("TBName")).Text;       
   
   
   
    
   
   
   
    
   
   
   
               int ParentId = Convert.ToInt32(((DropDownList)gvStudent2.Rows[e.RowIndex].FindControl("DDLParentStu")).SelectedValue);//获取选中的父级名字对应的父ID  
   
   
   
               SqlConnection conn = new SqlConnection(StrConn);  
   
   
   
    
   
   
   
               conn.Open();  
   
   
   
    
   
   
   
               string sql = "update Category set  name='" + name + "', parentId=" + ParentId + "  where id=" + id;  //更改当前表中的 name 以及 父ID  
   
   
   
                
   
   
   
    
   
   
   
               SqlCommand cmd = new SqlCommand(sql, conn);  
   
   
   
               cmd.ExecuteNonQuery();  
   
   
   
               cmd.Dispose();  
   
   
   
               if (conn.State.ToString() == "open")  
   
   
   
                   conn.Close();  
   
   
   
    
   
   
   
               gvStudent2.EditIndex = -1;  
   
   
   
               GridViewBind();  
   
   
   
           }  
   
   
   
           catch (Exception ex)  
   
   
   
           {  
   
   
   
               Response.Write("数据库错误，错误缘由：" + ex.Message);  
   
   
   
               Response.End();  
   
   
   
           }  
   
   
   
       }  
   
   
   
       protected void gvStudent2_SelectedIndexChanging(object sender, GridViewSelectEventArgs e)  
   
   
   
       {  
   
   
   
    
   
   
   
       }  
   
   
   
    
   
   
   
       private void GridViewBind()  
   
   
   
       {  
   
   
   
           string StrConn = ConfigurationManager.ConnectionStrings["MyConnectionString"].ConnectionString.ToString();    //在web.config中定义过了connectionString  
   
   
   
         
   
   
   
           string sqlStr = "select  A.id,A.name,A.parentId as Pid,B.name as PName from Category A inner join Category B on a.parentId=b.id"; //自身链接，经过本表中绑定的父ID，将对应的父级名字显示出  
   
   
   
           DataSet ds = new DataSet();  
   
   
   
           try  
   
   
   
           {  
   
   
   
               SqlConnection conn = new SqlConnection(StrConn);  
   
   
   
    
   
   
   
               conn.Open();  
   
   
   
               SqlDataAdapter da = new SqlDataAdapter(sqlStr, conn);  
   
   
   
               da.Fill(ds);  
   
   
   
               conn.Close();  
   
   
   
               DataTable tb = ds.Tables[0];  
   
   
   
    
   
   
   
               gvStudent2.DataSource = tb;  
   
   
   
               gvStudent2.DataBind();  
   
   
   
           }  
   
   
   
           catch (Exception ex)  
   
   
   
           {  
   
   
   
               Response.Write("数据库错误，错误缘由：" + ex.Message);  
   
   
   
               Response.End();  
   
   
   
           }  
   
   
   
    
   
   
   
       }  
   
   
   
   }

web.config 中的配置sql