近来使用Gridview中的单元格编辑功能，参考前面的博客。发现在使用中存在着如下的注意事项
：
1.SqlDataSource必须包含着UpdateCommand并且要包含主键，尤其注意的是在相关联的Gridview中有DataKeyNames="EmployeeID"这个属性。
2.在gridview中自动添加的模板中有<asp:Label ID="Label1" runat="server" Text='<%# Bind("LastName") %>'>，但是必须注意bind与Eval的区别问题。不然会出现如下的问题
在RowUpdating事件中Item has already been added. Key in dictionary: 'LastName' Key being added: 'LastName'。解决方式：bind对应着e.NewValues[_columnKeys[i-2]] = value;，而eval须对应e.NewValues.Add(key, value);
此文中再一次把相关代码附上：
代码
/*为了方便，我们称Label为显示控件，TextBox或DropDownList为编辑控件*/
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;
public partial class Control_EditIndividualCell : System.Web.UI.Page
{
private const int _firstEditCellIndex = 2;
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
this.GridView1.DataBind();
}
if (this.GridView1.SelectedIndex > -1)
{
// 调用GridView的UpdateRow方法
this.GridView1.UpdateRow(this.GridView1.SelectedIndex, false);
}
}
protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
// 从第一个单元格内获得LinkButton控件
LinkButton _singleClickButton = (LinkButton)e.Row.Cells[0].Controls[0];
// 返回一个字符串，表示对包含目标控件的 ID 和事件参数的回发函数的 JavaScript 调用
string _jsSingle = ClientScript.GetPostBackClientHyperlink(_singleClickButton, "");
// 给每一个可编辑的单元格增加事件
for (int columnIndex = _firstEditCellIndex; columnIndex < e.Row.Cells.Count; columnIndex++)
{
// 增加列索引作为事件参数
string js = _jsSingle.Insert(_jsSingle.Length - 2, columnIndex.ToString());
// 给单元格增加onclick事件
e.Row.Cells[columnIndex].Attributes["onclick"] = js;
// 给单元格增加鼠标经过时指针样式
e.Row.Cells[columnIndex].Attributes["style"] += "cursor:pointer;cursor:hand;";
}
}
}
protected void GridView1_RowCommand(object sender, GridViewCommandEventArgs e)
{
GridView _gridView = (GridView)sender;
switch (e.CommandName)
{
case ("SingleClick"):
// 获得行索引
int _rowIndex = int.Parse(e.CommandArgument.ToString());
// 解析事件参数（在RowDataBound中增加的），从而获得被选中的列的索引
int _columnIndex = int.Parse(Request.Form["__EVENTARGUMENT"]);
// 设置GridView被选中的行的索引（每次回发后判断GridView1.SelectedIndex > -1则更新）
_gridView.SelectedIndex = _rowIndex;
// 绑定
_gridView.DataBind();
// 事件记录
this.Message.Text += "单击GridView的行的索引为：" + _rowIndex.ToString()
+ "；列索引为：" + _columnIndex + "<br />";
// 获得被选中单元格的显示控件并设置其不可见
Control _displayControl = _gridView.Rows[_rowIndex].Cells[_columnIndex].Controls[1];
_displayControl.Visible = false;
// 获得被选中单元格的编辑控件并设置其可见
Control _editControl = _gridView.Rows[_rowIndex].Cells[_columnIndex].Controls[3];
_editControl.Visible = true;
// 清除被选中单元格属性以删除click事件
_gridView.Rows[_rowIndex].Cells[_columnIndex].Attributes.Clear();
// 设置焦点到被选中的编辑控件
ClientScript.RegisterStartupScript(GetType(), "SetFocus",
"<script>document.getElementById('" + _editControl.ClientID + "').focus();</script>");
// 如果编辑控件是DropDownList的话，那么把SelectedValue设置为显示控件的值
if (_editControl is DropDownList && _displayControl is Label)
{
((DropDownList)_editControl).SelectedValue = ((Label)_displayControl).Text;
}
// 如果编辑控件是TextBox的话则选中文本框内文本
if (_editControl is TextBox)
{
((TextBox)_editControl).Attributes.Add("onfocus", "this.select()");
}
break;
}
}
/// <summary>
/// 把值（values）从EditItemTemplate转移到NewValues集合里（使用数据源控件的话就需要这步）
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
protected void GridView1_RowUpdating(object sender, GridViewUpdateEventArgs e)
{
GridView _gridView = (GridView)sender;
string key = "";
string value = "";
// NewValues集合里的key
string[] _columnKeys = new string[] { "LastName", "FirstName", "Country" };
if (e.RowIndex > -1)
{
// 循环每一列
for (int i = _firstEditCellIndex; i < _gridView.Columns.Count; i++)
{
// 获得单元格里的控件
Control _displayControl = _gridView.Rows[e.RowIndex].Cells[i].Controls[1];
Control _editControl = _gridView.Rows[e.RowIndex].Cells[i].Controls[3];
// 获得列的key
key = _columnKeys[i - _firstEditCellIndex];
// 如果单元格处于编辑模式的话，那么从编辑控件中获取值
if (_editControl.Visible)
{
if (_editControl is TextBox)
{
value = ((TextBox)_editControl).Text;
}
else if (_editControl is DropDownList)
{
value = ((DropDownList)_editControl).SelectedValue;
}
// 增加key/value对到NewValues集合
e.NewValues.Add(key, value);
}
// 否则从显示控件中获取值
else
{
value = ((Label)_displayControl).Text.ToString();
// 增加key/value对到NewValues集合
e.NewValues.Add(key, value);
}
}
}
}
// 注册动态创建的客户端脚本
protected override void Render(HtmlTextWriter writer)
{
// 在RowDataBound中创建的自定义事件必须要在页中注册
// 通过重写Render方法来调用ClientScriptManager.RegisterForEventValidation。
// 通过GridViewRow.UniqueID返回行的唯一ID，按纽的唯一ID通过在行的唯一ID后附加“$ct100”而生成。
foreach (GridViewRow r in GridView1.Rows)
{
if (r.RowType == DataControlRowType.DataRow)
{
for (int columnIndex = _firstEditCellIndex; columnIndex < r.Cells.Count; columnIndex++)
{
Page.ClientScript.RegisterForEventValidation(r.UniqueID + "$ctl00", columnIndex.ToString());
}
}
}
base.Render(writer);
}
}
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;
public partial class Control_EditIndividualCell : System.Web.UI.Page
{
private const int _firstEditCellIndex = 2;
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
this.GridView1.DataBind();
}
if (this.GridView1.SelectedIndex > -1)
{
// 调用GridView的UpdateRow方法
this.GridView1.UpdateRow(this.GridView1.SelectedIndex, false);
}
}
protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
// 从第一个单元格内获得LinkButton控件
LinkButton _singleClickButton = (LinkButton)e.Row.Cells[0].Controls[0];
// 返回一个字符串，表示对包含目标控件的 ID 和事件参数的回发函数的 JavaScript 调用
string _jsSingle = ClientScript.GetPostBackClientHyperlink(_singleClickButton, "");
// 给每一个可编辑的单元格增加事件
for (int columnIndex = _firstEditCellIndex; columnIndex < e.Row.Cells.Count; columnIndex++)
{
// 增加列索引作为事件参数
string js = _jsSingle.Insert(_jsSingle.Length - 2, columnIndex.ToString());
// 给单元格增加onclick事件
e.Row.Cells[columnIndex].Attributes["onclick"] = js;
// 给单元格增加鼠标经过时指针样式
e.Row.Cells[columnIndex].Attributes["style"] += "cursor:pointer;cursor:hand;";
}
}
}
protected void GridView1_RowCommand(object sender, GridViewCommandEventArgs e)
{
GridView _gridView = (GridView)sender;
switch (e.CommandName)
{
case ("SingleClick"):
// 获得行索引
int _rowIndex = int.Parse(e.CommandArgument.ToString());
// 解析事件参数（在RowDataBound中增加的），从而获得被选中的列的索引
int _columnIndex = int.Parse(Request.Form["__EVENTARGUMENT"]);
// 设置GridView被选中的行的索引（每次回发后判断GridView1.SelectedIndex > -1则更新）
_gridView.SelectedIndex = _rowIndex;
// 绑定
_gridView.DataBind();
// 事件记录
this.Message.Text += "单击GridView的行的索引为：" + _rowIndex.ToString()
+ "；列索引为：" + _columnIndex + "<br />";
// 获得被选中单元格的显示控件并设置其不可见
Control _displayControl = _gridView.Rows[_rowIndex].Cells[_columnIndex].Controls[1];
_displayControl.Visible = false;
// 获得被选中单元格的编辑控件并设置其可见
Control _editControl = _gridView.Rows[_rowIndex].Cells[_columnIndex].Controls[3];
_editControl.Visible = true;
// 清除被选中单元格属性以删除click事件
_gridView.Rows[_rowIndex].Cells[_columnIndex].Attributes.Clear();
// 设置焦点到被选中的编辑控件
ClientScript.RegisterStartupScript(GetType(), "SetFocus",
"<script>document.getElementById('" + _editControl.ClientID + "').focus();</script>");
// 如果编辑控件是DropDownList的话，那么把SelectedValue设置为显示控件的值
if (_editControl is DropDownList && _displayControl is Label)
{
((DropDownList)_editControl).SelectedValue = ((Label)_displayControl).Text;
}
// 如果编辑控件是TextBox的话则选中文本框内文本
if (_editControl is TextBox)
{
((TextBox)_editControl).Attributes.Add("onfocus", "this.select()");
}
break;
}
}
/// <summary>
/// 把值（values）从EditItemTemplate转移到NewValues集合里（使用数据源控件的话就需要这步）
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
protected void GridView1_RowUpdating(object sender, GridViewUpdateEventArgs e)
{
GridView _gridView = (GridView)sender;
string key = "";
string value = "";
// NewValues集合里的key
string[] _columnKeys = new string[] { "LastName", "FirstName", "Country" };
if (e.RowIndex > -1)
{
// 循环每一列
for (int i = _firstEditCellIndex; i < _gridView.Columns.Count; i++)
{
// 获得单元格里的控件
Control _displayControl = _gridView.Rows[e.RowIndex].Cells[i].Controls[1];
Control _editControl = _gridView.Rows[e.RowIndex].Cells[i].Controls[3];
// 获得列的key
key = _columnKeys[i - _firstEditCellIndex];
// 如果单元格处于编辑模式的话，那么从编辑控件中获取值
if (_editControl.Visible)
{
if (_editControl is TextBox)
{
value = ((TextBox)_editControl).Text;
}
else if (_editControl is DropDownList)
{
value = ((DropDownList)_editControl).SelectedValue;
}
// 增加key/value对到NewValues集合
e.NewValues.Add(key, value);
}
// 否则从显示控件中获取值
else
{
value = ((Label)_displayControl).Text.ToString();
// 增加key/value对到NewValues集合
e.NewValues.Add(key, value);
}
}
}
}
// 注册动态创建的客户端脚本
protected override void Render(HtmlTextWriter writer)
{
// 在RowDataBound中创建的自定义事件必须要在页中注册
// 通过重写Render方法来调用ClientScriptManager.RegisterForEventValidation。
// 通过GridViewRow.UniqueID返回行的唯一ID，按纽的唯一ID通过在行的唯一ID后附加“$ct100”而生成。
foreach (GridViewRow r in GridView1.Rows)
{
if (r.RowType == DataControlRowType.DataRow)
{
for (int columnIndex = _firstEditCellIndex; columnIndex < r.Cells.Count; columnIndex++)
{
Page.ClientScript.RegisterForEventValidation(r.UniqueID + "$ctl00", columnIndex.ToString());
}
}
}
base.Render(writer);
}
}
代码
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="EditIndividualCell.aspx.cs" Inherits="Control_EditIndividualCell" %>
<!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 id="Head1" runat="server">
<title>在GridView中针对鼠标单击的某一独立单元格进行编辑</title>
</head>
<body>
<form id="form1" runat="server">
<div>
<asp:GridView ID="GridView1" runat="server" AllowPaging="True" AutoGenerateColumns="False"
DataKeyNames="EmployeeID" DataSourceID="SqlDataSource1" AllowSorting="True" OnRowCommand="GridView1_RowCommand"
OnRowDataBound="GridView1_RowDataBound" OnRowUpdating="GridView1_RowUpdating">
<Columns>
<asp:ButtonField Text="SingleClick" CommandName="SingleClick" Visible="False" />
<asp:BoundField DataField="EmployeeID" HeaderText="EmployeeID" InsertVisible="False"
ReadOnly="True" SortExpression="EmployeeID" />
<asp:TemplateField HeaderText="LastName" SortExpression="LastName">
<ItemTemplate>
<asp:Label ID="lblLastName" runat="server" Text='<%# Eval("LastName") %>'></asp:Label>
<asp:TextBox ID="txtLastName" runat="server" Text='<%# Eval("LastName") %>' Visible="false"></asp:TextBox>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="FirstName" SortExpression="FirstName">
<ItemTemplate>
<asp:Label ID="lblFirstName" runat="server" Text='<%# Eval("FirstName") %>'></asp:Label>
<asp:TextBox ID="txtFirstName" runat="server" Text='<%# Eval("FirstName") %>' Visible="false"></asp:TextBox>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Country" SortExpression="Country">
<ItemTemplate>
<asp:Label ID="lblCountry" runat="server" Text='<%# Eval("Country") %>'></asp:Label>
<asp:DropDownList ID="ddlCountry" runat="server" Visible="False" AutoPostBack="True"
DataSourceID="SqlDataSource1" DataTextField="Country" DataValueField="Country">
</asp:DropDownList><asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString="<%$ ConnectionStrings:NorthwindConnectionString %>"
SelectCommand="SELECT DISTINCT [Country] FROM [Employees]"></asp:SqlDataSource>
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
<asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString="<%$ ConnectionStrings:NorthwindConnectionString %>"
DeleteCommand="DELETE FROM [Employees] WHERE [EmployeeID] = @EmployeeID" InsertCommand="INSERT INTO [Employees] ([LastName], [FirstName], [Country]) VALUES (@LastName, @FirstName, @Country)"
SelectCommand="SELECT [LastName], [FirstName], [Country], [EmployeeID] FROM [Employees]"
UpdateCommand="UPDATE [Employees] SET [LastName] = @LastName, [FirstName] = @FirstName, [Country] = @Country WHERE [EmployeeID] = @EmployeeID">
<DeleteParameters>
<asp:Parameter Name="EmployeeID" Type="Int32" />
</DeleteParameters>
<UpdateParameters>
<asp:Parameter Name="LastName" Type="String" />
<asp:Parameter Name="FirstName" Type="String" />
<asp:Parameter Name="Country" Type="String" />
<asp:Parameter Name="EmployeeID" Type="Int32" />
</UpdateParameters>
<InsertParameters>
<asp:Parameter Name="LastName" Type="String" />
<asp:Parameter Name="FirstName" Type="String" />
<asp:Parameter Name="Country" Type="String" />
</InsertParameters>
</asp:SqlDataSource>
<br />
<br />
<asp:Label ID="Message" runat="server" ForeColor="Red" Font-Bold="true"></asp:Label>
</div>
</form>
</body>
</html>
<!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 id="Head1" runat="server">
<title>在GridView中针对鼠标单击的某一独立单元格进行编辑</title>
</head>
<body>
<form id="form1" runat="server">
<div>
<asp:GridView ID="GridView1" runat="server" AllowPaging="True" AutoGenerateColumns="False"
DataKeyNames="EmployeeID" DataSourceID="SqlDataSource1" AllowSorting="True" OnRowCommand="GridView1_RowCommand"
OnRowDataBound="GridView1_RowDataBound" OnRowUpdating="GridView1_RowUpdating">
<Columns>
<asp:ButtonField Text="SingleClick" CommandName="SingleClick" Visible="False" />
<asp:BoundField DataField="EmployeeID" HeaderText="EmployeeID" InsertVisible="False"
ReadOnly="True" SortExpression="EmployeeID" />
<asp:TemplateField HeaderText="LastName" SortExpression="LastName">
<ItemTemplate>
<asp:Label ID="lblLastName" runat="server" Text='<%# Eval("LastName") %>'></asp:Label>
<asp:TextBox ID="txtLastName" runat="server" Text='<%# Eval("LastName") %>' Visible="false"></asp:TextBox>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="FirstName" SortExpression="FirstName">
<ItemTemplate>
<asp:Label ID="lblFirstName" runat="server" Text='<%# Eval("FirstName") %>'></asp:Label>
<asp:TextBox ID="txtFirstName" runat="server" Text='<%# Eval("FirstName") %>' Visible="false"></asp:TextBox>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Country" SortExpression="Country">
<ItemTemplate>
<asp:Label ID="lblCountry" runat="server" Text='<%# Eval("Country") %>'></asp:Label>
<asp:DropDownList ID="ddlCountry" runat="server" Visible="False" AutoPostBack="True"
DataSourceID="SqlDataSource1" DataTextField="Country" DataValueField="Country">
</asp:DropDownList><asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString="<%$ ConnectionStrings:NorthwindConnectionString %>"
SelectCommand="SELECT DISTINCT [Country] FROM [Employees]"></asp:SqlDataSource>
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
<asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString="<%$ ConnectionStrings:NorthwindConnectionString %>"
DeleteCommand="DELETE FROM [Employees] WHERE [EmployeeID] = @EmployeeID" InsertCommand="INSERT INTO [Employees] ([LastName], [FirstName], [Country]) VALUES (@LastName, @FirstName, @Country)"
SelectCommand="SELECT [LastName], [FirstName], [Country], [EmployeeID] FROM [Employees]"
UpdateCommand="UPDATE [Employees] SET [LastName] = @LastName, [FirstName] = @FirstName, [Country] = @Country WHERE [EmployeeID] = @EmployeeID">
<DeleteParameters>
<asp:Parameter Name="EmployeeID" Type="Int32" />
</DeleteParameters>
<UpdateParameters>
<asp:Parameter Name="LastName" Type="String" />
<asp:Parameter Name="FirstName" Type="String" />
<asp:Parameter Name="Country" Type="String" />
<asp:Parameter Name="EmployeeID" Type="Int32" />
</UpdateParameters>
<InsertParameters>
<asp:Parameter Name="LastName" Type="String" />
<asp:Parameter Name="FirstName" Type="String" />
<asp:Parameter Name="Country" Type="String" />
</InsertParameters>
</asp:SqlDataSource>
<br />
<br />
<asp:Label ID="Message" runat="server" ForeColor="Red" Font-Bold="true"></asp:Label>
</div>
</form>
</body>
</html>