GridView.RowEditing Событие
Определение
Важно!
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Происходит при щелчке по кнопке "Править" в строке, но до входа элемента управления в режим правки GridView.
public:
event System::Web::UI::WebControls::GridViewEditEventHandler ^ RowEditing;
public event System.Web.UI.WebControls.GridViewEditEventHandler RowEditing;
member this.RowEditing : System.Web.UI.WebControls.GridViewEditEventHandler
Public Custom Event RowEditing As GridViewEditEventHandler
Тип события
Примеры
В следующем примере показано, как использовать RowEditing событие , чтобы поместить строку в режим редактирования, когда источник данных задается программным способом.
<%@ Page Language="C#" %>
<%@ Import Namespace="System.Data" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
protected void Page_Load(object sender, EventArgs e)
{
if (!Page.IsPostBack)
{
// Create a new table.
DataTable taskTable = new DataTable("TaskList");
// Create the columns.
taskTable.Columns.Add("Id", typeof(int));
taskTable.Columns.Add("Description", typeof(string));
taskTable.Columns.Add("IsComplete", typeof(bool) );
//Add data to the new table.
for (int i = 0; i < 20; i++)
{
DataRow tableRow = taskTable.NewRow();
tableRow["Id"] = i;
tableRow["Description"] = "Task " + i.ToString();
tableRow["IsComplete"] = false;
taskTable.Rows.Add(tableRow);
}
//Persist the table in the Session object.
Session["TaskTable"] = taskTable;
//Bind data to the GridView control.
BindData();
}
}
protected void TaskGridView_PageIndexChanging(object sender, GridViewPageEventArgs e)
{
TaskGridView.PageIndex = e.NewPageIndex;
//Bind data to the GridView control.
BindData();
}
protected void TaskGridView_RowEditing(object sender, GridViewEditEventArgs e)
{
//Set the edit index.
TaskGridView.EditIndex = e.NewEditIndex;
//Bind data to the GridView control.
BindData();
}
protected void TaskGridView_RowCancelingEdit(object sender, GridViewCancelEditEventArgs e)
{
//Reset the edit index.
TaskGridView.EditIndex = -1;
//Bind data to the GridView control.
BindData();
}
protected void TaskGridView_RowUpdating(object sender, GridViewUpdateEventArgs e)
{
//Retrieve the table from the session object.
DataTable dt = (DataTable)Session["TaskTable"];
//Update the values.
GridViewRow row = TaskGridView.Rows[e.RowIndex];
dt.Rows[row.DataItemIndex]["Id"] = ((TextBox)(row.Cells[1].Controls[0])).Text;
dt.Rows[row.DataItemIndex]["Description"] = ((TextBox)(row.Cells[2].Controls[0])).Text;
dt.Rows[row.DataItemIndex]["IsComplete"] = ((CheckBox)(row.Cells[3].Controls[0])).Checked;
//Reset the edit index.
TaskGridView.EditIndex = -1;
//Bind data to the GridView control.
BindData();
}
private void BindData()
{
TaskGridView.DataSource = Session["TaskTable"];
TaskGridView.DataBind();
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title>GridView example</title>
</head>
<body>
<form id="form1" runat="server">
<div>
<asp:GridView ID="TaskGridView" runat="server"
AutoGenerateEditButton="True"
AllowPaging="true"
OnRowEditing="TaskGridView_RowEditing"
OnRowCancelingEdit="TaskGridView_RowCancelingEdit"
OnRowUpdating="TaskGridView_RowUpdating"
OnPageIndexChanging="TaskGridView_PageIndexChanging">
</asp:GridView>
</div>
</form>
</body>
</html>
<%@ Page Language="VB" %>
<%@ Import Namespace="System.Data" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
Protected Sub Page_Load()
If Not Page.IsPostBack Then
' Create a new table.
Dim taskTable As New DataTable("TaskList")
' Create the columns.
taskTable.Columns.Add("Id", GetType(Integer))
taskTable.Columns.Add("Description", GetType(String))
taskTable.Columns.Add("IsComplete", GetType(Boolean))
'Add data to the new table.
For i = 0 To 19
Dim tableRow = taskTable.NewRow()
tableRow("Id") = i
tableRow("Description") = "Task " + i.ToString()
tableRow("IsComplete") = False
taskTable.Rows.Add(tableRow)
Next
'Persist the table in the Session object.
Session("TaskTable") = taskTable
'Bind data to the GridView control.
BindData()
End If
End Sub
Protected Sub TaskGridView_PageIndexChanging(ByVal sender As Object, ByVal e As GridViewPageEventArgs)
TaskGridView.PageIndex = e.NewPageIndex
'Bind data to the GridView control.
BindData()
End Sub
Protected Sub TaskGridView_RowEditing(ByVal sender As Object, ByVal e As GridViewEditEventArgs)
'Set the edit index.
TaskGridView.EditIndex = e.NewEditIndex
'Bind data to the GridView control.
BindData()
End Sub
Protected Sub TaskGridView_RowCancelingEdit()
'Reset the edit index.
TaskGridView.EditIndex = -1
'Bind data to the GridView control.
BindData()
End Sub
Protected Sub TaskGridView_RowUpdating(ByVal sender As Object, ByVal e As GridViewUpdateEventArgs)
'Retrieve the table from the session object.
Dim dt = CType(Session("TaskTable"), DataTable)
'Update the values.
Dim row = TaskGridView.Rows(e.RowIndex)
dt.Rows(row.DataItemIndex)("Id") = (CType((row.Cells(1).Controls(0)), TextBox)).Text
dt.Rows(row.DataItemIndex)("Description") = (CType((row.Cells(2).Controls(0)), TextBox)).Text
dt.Rows(row.DataItemIndex)("IsComplete") = (CType((row.Cells(3).Controls(0)), CheckBox)).Checked
'Reset the edit index.
TaskGridView.EditIndex = -1
'Bind data to the GridView control.
BindData()
End Sub
Private Sub BindData()
TaskGridView.DataSource = Session("TaskTable")
TaskGridView.DataBind()
End Sub
</script>
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title>GridView example</title>
</head>
<body>
<form id="form1" runat="server">
<div>
<asp:GridView ID="TaskGridView" runat="server"
AutoGenerateEditButton="True"
AllowPaging="true"
OnRowEditing="TaskGridView_RowEditing"
OnRowCancelingEdit="TaskGridView_RowCancelingEdit"
OnRowUpdating="TaskGridView_RowUpdating"
OnPageIndexChanging="TaskGridView_PageIndexChanging">
</asp:GridView>
</div>
</form>
</body>
</html>
В следующем примере показано, как использовать RowEditing событие для отмены операции редактирования, если пользователь пытается изменить запись для компании в США.
<%@ Page language="C#" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
void CustomersGridView_RowEditing(Object sender, GridViewEditEventArgs e)
{
// Get the country for the row being edited. For this example, the
// country is contained in the seventh column (index 6).
String country = CustomersGridView.Rows[e.NewEditIndex].Cells[6].Text;
// For this example, cancel the edit operation if the user attempts
// to edit the record of a customer from the Unites States.
if (country == "USA")
{
// Cancel the edit operation.
e.Cancel = true;
Message.Text = "You cannot edit this record.";
}
else
{
Message.Text = "";
}
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>GridView RowEditing Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>GridView RowEditing Example</h3>
<asp:label id="Message"
forecolor="Red"
runat="server"/>
<br/>
<!-- The GridView control automatically sets the columns -->
<!-- specified in the datakeynames property as read-only. -->
<!-- No input controls are rendered for these columns in -->
<!-- edit mode. -->
<asp:gridview id="CustomersGridView"
datasourceid="CustomersSqlDataSource"
autogeneratecolumns="true"
autogenerateeditbutton="true"
allowpaging="true"
datakeynames="CustomerID"
onrowediting="CustomersGridView_RowEditing"
runat="server">
</asp:gridview>
<!-- This example uses Microsoft SQL Server and connects -->
<!-- to the Northwind sample database. Use an ASP.NET -->
<!-- expression to retrieve the connection string value -->
<!-- from the Web.config file. -->
<asp:sqldatasource id="CustomersSqlDataSource"
selectcommand="Select [CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country] From [Customers]"
updatecommand="Update Customers SET CompanyName=@CompanyName, Address=@Address, City=@City, PostalCode=@PostalCode, Country=@Country WHERE (CustomerID = @CustomerID)"
connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>"
runat="server">
</asp:sqldatasource>
</form>
</body>
</html>
<%@ Page language="VB" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
Sub CustomersGridView_RowEditing(ByVal sender As Object, ByVal e As GridViewEditEventArgs)
' Get the country for the row being edited. For this example, the
' country is contained in the seventh column (index 6).
Dim country As String = CustomersGridView.Rows(e.NewEditIndex).Cells(6).Text
' For this example, cancel the edit operation if the user attempts
' to edit the record of a customer from the United States.
If country = "USA" Then
' Cancel the edit operation.
e.Cancel = True
Message.Text = "You cannot edit this record."
Else
Message.Text = ""
End If
End Sub
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>GridView RowEditing Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>GridView RowEditing Example</h3>
<asp:label id="Message"
forecolor="Red"
runat="server"/>
<br/>
<!-- The GridView control automatically sets the columns -->
<!-- specified in the datakeynames property as read-only. -->
<!-- No input controls are rendered for these columns in -->
<!-- edit mode. -->
<asp:gridview id="CustomersGridView"
datasourceid="CustomersSqlDataSource"
autogeneratecolumns="true"
autogenerateeditbutton="true"
allowpaging="true"
datakeynames="CustomerID"
onrowediting="CustomersGridView_RowEditing"
runat="server">
</asp:gridview>
<!-- This example uses Microsoft SQL Server and connects -->
<!-- to the Northwind sample database. Use an ASP.NET -->
<!-- expression to retrieve the connection string value -->
<!-- from the Web.config file. -->
<asp:sqldatasource id="CustomersSqlDataSource"
selectcommand="Select [CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country] From [Customers]"
updatecommand="Update Customers SET CompanyName=@CompanyName, Address=@Address, City=@City, PostalCode=@PostalCode, Country=@Country WHERE (CustomerID = @CustomerID)"
connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>"
runat="server">
</asp:sqldatasource>
</form>
</body>
</html>
Комментарии
Событие RowEditing возникает при нажатии кнопки Изменить строки, но до того, как элемент управления перейдет в GridView режим редактирования. Это позволяет предоставить метод обработки событий, который выполняет настраиваемую подпрограмму, например отмену операции редактирования при каждом возникновении этого события.
Объект GridViewEditEventArgs передается методу обработки событий, который позволяет определить индекс текущей строки и указать, что операция редактирования должна быть отменена. Чтобы отменить операцию редактирования, задайте Cancel для свойства GridViewEditEventArgs объекта значение true
.
Дополнительные сведения об обработке событий см. в разделе Обработка и вызов событий.