我在页面上有问题，在gdvCar_DataBound我添加了三个按钮，当我点击其中任何一个时，页面转到回发但没有输入gdvCar_RowCommand然后那些按钮（以及我在gdvCar_DataBound中添加的图像） disaper。然后网格就像gdvCar_DataBound不执行一样。我的问题是为什么它没有进入gdvCar_RowCommand？
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using HMS.library;
using System.Data.SqlClient;
namespace HMS
{
public partial class Cars : System.Web.UI.Page
{
#region fields
private const Int16 PageId = 1;
private String connectionString = "Server=localhost;Database=hms_test;Trusted_Connection=True;";
String[] filters = null;
#endregion
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
FillProducer();
FillModel(Convert.ToInt16(ddlProducer.SelectedValue));
RestoreFilters();
FillGrid();
}
}
#region events
protected void ddlProducer_Changed(object sender, EventArgs e)
{
if (ddlProducer.SelectedValue != "0")
{
ddlModel.Enabled = true;
FillModel(Convert.ToInt16(ddlProducer.SelectedValue));
}
else
{
ddlModel.SelectedValue = "0";
ddlModel.Enabled = false;
}
upSearch.Update();
}
protected void gdvCar_RowCommand(object sender, GridViewCommandEventArgs e)
{
switch (e.CommandName)
{
case "Reserve":
{
pnlReserve.Visible = true;
break;
}
case "Phone":
{
break;
}
case "Email":
{
break;
}
}
}
protected void gdvCar_DataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
String id = e.Row.Cells[0].Text;
Image img = new Image();
img.ID = "img_one" + id;
img.Width = 96;
img.Height = 96;
img.ImageUrl = "images/car/" + e.Row.Cells[7].Text;
e.Row.Cells[7].Controls.Add(img);
img = new Image();
img.ID = "img_two" + id;
img.Width = 96;
img.Height = 96;
img.ImageUrl = "images/car/" + e.Row.Cells[8].Text;
e.Row.Cells[8].Controls.Add(img);
img = new Image();
img.ID = "img_three" + id;
img.Width = 96;
img.Height = 96;
img.ImageUrl = "images/car/" + e.Row.Cells[9].Text;
e.Row.Cells[9].Controls.Add(img);
ImageButton imbReserve = new ImageButton();
imbReserve.ID = "res" + id;
imbReserve.Enabled = true;
imbReserve.Width = 48; imbReserve.Height = 48;
imbReserve.ToolTip = "Reserve"; imbReserve.AlternateText = "Reserve";
imbReserve.ImageUrl = "images/icons/key.gif";
imbReserve.CommandName = "Reserve";
imbReserve.CommandArgument = id;
e.Row.Cells[10].Controls.Add(imbReserve);
ImageButton imbPhone = new ImageButton();
imbPhone.ID = "phone" + id;
imbPhone.Enabled = true;
imbPhone.Width = 48; imbPhone.Height = 48;
imbPhone.ToolTip = "Reserve by phone"; imbPhone.AlternateText = "Phone";
imbPhone.ImageUrl = "images/icons/phone.jpg";
imbPhone.CommandName = "Phone";
imbPhone.CommandArgument = id;
e.Row.Cells[11].Controls.Add(imbPhone);
ImageButton imbEmail = new ImageButton();
imbEmail.ID = "email" + id;
imbEmail.Enabled = true;
imbEmail.Width = 48; imbEmail.Height = 48;
imbEmail.ToolTip = "Reserve by email"; imbEmail.AlternateText = "Email";
imbEmail.ImageUrl = "images/icons/email.jpg";
imbEmail.CommandName = "Email";
imbEmail.CommandArgument = id;
e.Row.Cells[12].Controls.Add(imbEmail);
}
}
protected void imbSearch_Click(object sender, ImageClickEventArgs e)
{
StoreFilters();
FillGrid();
}
#endregion
#region functions
private void FillProducer()
{
hmsDataContext hms = new hmsDataContext();
var source = from o in hms.producer_cars
orderby o.name
select new
{
o.id,
o.name
};
foreach (var temp in source)
ddlProducer.Items.Add(new ListItem(temp.name, temp.id.ToString()));
ddlProducer.Items.Insert(0, (new ListItem("all producers", "0")));
}
private void FillModel(int producer_id)
{
hmsDataContext hms = new hmsDataContext();
var source = from o in hms.model_cars
from p in hms.producer_cars
where o.producer_car_id == producer_id && p.id == producer_id
orderby o.name
select new
{
o.id,
o.name
};
ddlModel.Items.Clear();
foreach (var temp in source)
ddlModel.Items.Add(new ListItem(temp.name, temp.id.ToString()));
ddlModel.Items.Insert(0, (new ListItem("all producers", "0")));
}
private void FillGrid()
{
SqlConnection conn = new SqlConnection(connectionString);
String command = @"SELECT car.id AS id, car.price as price, car.weight as weight,
car.year as year, producer_car.name as producer, model_car.name as model, car.number_seats as number_seats, car.photo_one as photo_one,car.photo_two as photo_two,car.photo_three as photo_three, '' as reserver,'' as phone,'' as email
FROM car INNER JOIN model_car on car.model_car_id=model_car.id
INNER JOIN producer_car on model_car.producer_car_id=producer_car.id";
if(filters!=null){
String[] search=new String[5];
search[0]=filters[0]!="0"?"producer_car.id="+filters[0]:"";
search[1]= filters[1] != "0" ? "model_car.id=" + filters[1] : "";
search[2]=filters[2]!=""?"car.color LIKE \'"+filters[2]+"\'":"";
search[3]=filters[3]!=""?"car.price<"+filters[3]:"";
search[4] = filters[4] != "" ? "car.number_seats=" + filters[4] : "";
var a=from f in search
where f!=""
select f;
String filterAddition="";
if(a.Count()>0){
filterAddition=" WHERE ";
foreach ( var b in a){
filterAddition+=" "+b+" AND";
}
filterAddition=filterAddition.EndsWith("AND")?filterAddition.Substring(0,filterAddition.Length-3):filterAddition;
}
command+=filterAddition;
}
SqlCommand comm = new SqlCommand(command, conn);
SqlDataReader r = null;
try
{
comm.Connection.Open();
r =comm.ExecuteReader();
gdvCar.DataSource = r;
gdvCar.DataBind();
r.Close();
}
catch (Exception exc)
{
throw (exc);
}
finally
{
conn.Close();
}
}
private void StoreFilters()
{
filters = new String[5];
filters[0] = ddlProducer.SelectedValue;
filters[1] = ddlModel.SelectedValue;
filters[2] = ddlColor.SelectedValue;
filters[3] = txtStartPrice.Text;
filters[4] = ddlNumber.SelectedValue;
Session["1"] = filters;
}
private void RestoreFilters()
{
if (Session["1"] != null)
{
filters = (String[])Session["1"];
ddlProducer.SelectedValue = filters[0];
ddlProducer_Changed(null, null);
ddlModel.SelectedValue = filters[1];
ddlColor.SelectedValue = filters[2];
txtStartPrice.Text = filters[3];
ddlNumber.SelectedValue = filters[4];
}
}
private void ReserveCar(String FirstName, String LastName, DateTime Start, DateTime End, String Visa, Int16 CarId)
{
hmsDataContext hms = new hmsDataContext();
var a = from c in hms.cars
from rc in hms.rented_cars
where c.id == rc.id_car && c.id == CarId
select new
{
start = rc.start,
end = rc.end
};
Boolean free = false;
if (a.Count() == 0)
{
free = true;
}
else if (a.Count() == 1)
{
if ((a.First().start > End) || (a.First().end < Start))
free = true;
}
else
{
if ((a.First().start > End) || (a.First().end < Start))
free = true;
else if(!free)
{
int n = a.Count();
for (int i = 0; (i < n - 1) && (!free); i++)
{
if (a.ElementAt(i).end < Start && a.ElementAt(i + 1).start > End)
free = true;
i++;
}
if (!free)
{
if (a.ElementAt(n - 1).end < Start)
free = true;
}
}
}
if (free)
{
//insert
}
else
{
//label-nije slobodno za taj termin
}
}
#endregion
}
}
ASPX
<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Cars.aspx.cs" Inherits="HMS.Cars"
MasterPageFile="~/frame.Master" %>
<%@ Register Assembly="AjaxControlToolkit" Namespace="AjaxControlToolkit" TagPrefix="asp" %>
<asp:Content ContentPlaceHolderID="content" ID="con" runat="server">
<link rel="StyleSheet" href="css/menu.css" type="text/css" media="all">
<asp:ScriptManager ID="sc" runat="server">
</asp:ScriptManager>
<div id="menu">
<ul class="glossymenu">
<li><a href="Home.aspx"><b>Home</b></a></li>
<li class="current"><a href="Cars.aspx"><b>Cars</b></a></li>
<li><a href="Boats.aspx"><b>Boats</b></a></li>
<li><a href="Contact.aspx"><b>Contact</b></a></li>
<li><a href="Admin.aspx"><b>Admin</b></a></li>
</ul>
</div>
<div>
<div>
<asp:UpdatePanel ID="upSearch" runat="server" UpdateMode="Conditional">
<ContentTemplate>
<div id="search">
<fieldset>
<legend>Advanced search</legend>
<table>
<tr>
<td>
Proizvođač:<asp:DropDownList ID="ddlProducer" runat="server" OnSelectedIndexChanged="ddlProducer_Changed"
AutoPostBack="true">
</asp:DropDownList>
</td>
<td>
Model:<asp:DropDownList ID="ddlModel" runat="server" Enabled="false">
</asp:DropDownList>
</td>
<td>
Boja:<asp:DropDownList ID="ddlColor" runat="server">
<asp:ListItem Text="all" Value=""></asp:ListItem>
<asp:ListItem Text="White" Value="white"></asp:ListItem>
<asp:ListItem Text="Green" Value="green"></asp:ListItem>
<asp:ListItem Text="White" Value="white"></asp:ListItem>
<asp:ListItem Text="Green" Value="green"></asp:ListItem>
<asp:ListItem Text="White" Value="white"></asp:ListItem>
<asp:ListItem Text="Green" Value="green"></asp:ListItem>
<asp:ListItem Text="White" Value="white"></asp:ListItem>
<asp:ListItem Text="Green" Value="green"></asp:ListItem>
<asp:ListItem Text="White" Value="white"></asp:ListItem>
<asp:ListItem Text="Green" Value="green"></asp:ListItem>
<asp:ListItem Text="White" Value="white"></asp:ListItem>
<asp:ListItem Text="Green" Value="green"></asp:ListItem>
</asp:DropDownList>
</td>
<td>
Cena do:
<asp:TextBox ID="txtStartPrice" runat="server" MaxLength="10"></asp:TextBox>
din/dan
</td>
<td>
Number seats:<asp:DropDownList ID="ddlNumber" runat="server">
<asp:ListItem Text="-- --" Value=""></asp:ListItem>
<asp:ListItem Text="1" Value="1"></asp:ListItem>
<asp:ListItem Text="2" Value="2"></asp:ListItem>
<asp:ListItem Text="3" Value="3"></asp:ListItem>
<asp:ListItem Text="4" Value="4"></asp:ListItem>
<asp:ListItem Text="5" Value="1"></asp:ListItem>
<asp:ListItem Text="6" Value="2"></asp:ListItem>
<asp:ListItem Text="7" Value="3"></asp:ListItem>
<asp:ListItem Text="8" Value="4"></asp:ListItem>
<asp:ListItem Text="9" Value="2"></asp:ListItem>
<asp:ListItem Text="10" Value="3"></asp:ListItem>
<asp:ListItem Text="11" Value="4"></asp:ListItem>
</asp:DropDownList>
</td>
<td>
<asp:ImageButton ID="imbSearch" runat="server" ImageUrl="images/icons/search.png"
Width="32" Height="32" ToolTip="Search by choosen criterions" AlternateText="Search"
OnClick="imbSearch_Click" />
</td>
</tr>
</table>
</fieldset>
</div>
</ContentTemplate>
</asp:UpdatePanel>
<br />
<br />
<div>
<asp:UpdatePanel ID="upGrid" runat="server" UpdateMode="Always">
<ContentTemplate>
<asp:GridView ID="gdvCar" runat="server" OnRowCommand="gdvCar_RowCommand"
OnRowDataBound="gdvCar_DataBound">
</asp:GridView>
</ContentTemplate>
</asp:UpdatePanel>
</div>
<div>
<asp:UpdatePanel ID="upTemp" runat="server"><ContentTemplate>
<asp:Panel ID="pnlReserve" runat="server" Visible="false" Width="400" Height="400">
<asp:UpdatePanel ID="upReserve" runat="server">
<ContentTemplate>
</ContentTemplate>
</asp:UpdatePanel>
</asp:Panel>
</ContentTemplate></asp:UpdatePanel>
</div>
</div>
</asp:Content>
答案 0 :(得分：0)
您必须在每个Postback上重新创建RowCreated中的按钮，否则它们的事件将不会触发。
在ViewState中保存RowDataBound所需的内容。在RowCreated中，基于Viewstate值在Postback上重新创建它们（RowDatabound只在Databinding上调用）。然后，所有控件都可以在page-lifecyle早期提供，以提升他们的活动。
答案 1 :(得分：0)
我相信你可以用更优雅的方式做到，看一看，
<asp:GridView ...>
<Columns>
<asp:BoundField HeaderText="Some Caption" DataField="Column name from the DataReader result"/>
...
<asp:TemplateField HeaderText="Image..">
<asp:Image runat="server" ImageUrl='<%# String.Format("images/car/{0}", Eval("The column name from the DataReader of the cell 7") %>' />
</asp:TemplateField>
<asp:TemplateField HeaderText="ImageButton..">
<asp:ImageButton runat="server" .../>
</asp:TemplateField>
</Columns>
</asp:GridView>
然后您不必在代码中添加按钮和图像，并且每次创建行时都要添加它们，您只需要从数据库中获取数据并设置gridview的DataSource，并且我想你也可以摆脱获取数据的代码并用SqlDataSource替换它。
看看这篇关于GridView的文章， http://msdn.microsoft.com/en-us/library/aa479353.aspx