GridViewCommandEventHandler Delegera
Definition
Viktigt
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Representerar den metod som hanterar händelsen för RowCommand en GridView kontroll.
public delegate void GridViewCommandEventHandler(System::Object ^ sender, GridViewCommandEventArgs ^ e);public delegate void GridViewCommandEventHandler(object sender, GridViewCommandEventArgs e);type GridViewCommandEventHandler = delegate of obj * GridViewCommandEventArgs -> unitPublic Delegate Sub GridViewCommandEventHandler(sender As Object, e As GridViewCommandEventArgs)Parametrar
- sender
- Object
Källan till händelsen.
Ett GridViewCommandEventArgs objekt som innehåller händelsedata.
Exempel
I följande exempel visas hur du programmatiskt lägger till ett GridViewCommandEventHandler ombud i RowCommand händelsen för en GridView kontroll.
<%@ 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 Page_Load(Object sender, EventArgs e)
{
// Create a new GridView object.
GridView customersGridView = new GridView();
// Set the GridView object's properties.
customersGridView.ID = "CustomersGridView";
customersGridView.DataSourceID = "CustomersSource";
customersGridView.AutoGenerateColumns = false;
// Dynamically create the columns for the GridView control.
ButtonField addColumn = new ButtonField();
addColumn.CommandName = "Add";
addColumn.Text = "Add";
addColumn.ButtonType = ButtonType.Link;
BoundField companyNameColumn = new BoundField();
companyNameColumn.DataField = "CompanyName";
companyNameColumn.HeaderText = "Company Name";
BoundField cityColumn = new BoundField();
cityColumn.DataField = "City";
cityColumn.HeaderText = "City";
// Add the columns to the Columns collection
// of the GridView control.
customersGridView.Columns.Add(addColumn);
customersGridView.Columns.Add(companyNameColumn);
customersGridView.Columns.Add(cityColumn);
// Programmatically register the event handling methods.
customersGridView.RowCommand += new GridViewCommandEventHandler(this.CustomersGridView_RowCommand);
customersGridView.RowCreated += new GridViewRowEventHandler(this.CustomersGridView_RowCreated);
// Add the GridView object to the Controls collection
// of the PlaceHolder control.
GridViewPlaceHolder.Controls.Add(customersGridView);
}
void CustomersGridView_RowCommand(Object sender, GridViewCommandEventArgs e)
{
// If multiple ButtonField columns are used, use the
// CommandName property to determine which button was clicked.
if(e.CommandName=="Add")
{
// Convert the row index stored in the CommandArgument
// property to an Integer.
int index = Convert.ToInt32(e.CommandArgument);
// Retrieve the row that contains the button clicked
// by the user from the Rows collection. Use the
// CommandSource property to access the GridView control.
GridView customersGridView = (GridView)e.CommandSource;
GridViewRow row = customersGridView.Rows[index];
// Create a new ListItem object for the customer in the row.
ListItem item = new ListItem();
item.Text = Server.HtmlDecode(row.Cells[1].Text) + " " + Server.HtmlDecode(row.Cells[2].Text);
// If the author is not already in the ListBox, add the ListItem
// object to the Items collection of a ListBox control.
if(!CustomersListBox.Items.Contains(item))
{
CustomersListBox.Items.Add(item);
}
}
}
void CustomersGridView_RowCreated(Object sender, GridViewRowEventArgs e)
{
// The GridViewCommandEventArgs class does not contain a
// property that indicates which row's command button was
// clicked. To identify which row was clicked, use the button's
// CommandArgument property by setting it to the row's index.
if(e.Row.RowType == DataControlRowType.DataRow)
{
// Retrieve the LinkButton control from the first column.
LinkButton addButton = (LinkButton)e.Row.Cells[0].Controls[0];
// Set the LinkButton's CommandArgument property with the
// row's index.
addButton.CommandArgument = e.Row.RowIndex.ToString();
}
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>GridViewCommandEventHandler Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>GridViewCommandEventHandler Example</h3>
<table width="100%">
<tr>
<td style="width:50%">
<asp:placeholder id="GridViewPlaceHolder"
runat="Server"/>
</td>
<td style="vertical-align:top; width:50%">
Customers: <br/>
<asp:listbox id="CustomersListBox"
runat="server"/>
</td>
</tr>
</table>
<!-- 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="CustomersSource"
selectcommand="Select [CustomerID], [CompanyName], [City] From [Customers]"
connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>"
runat="server"/>
</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 Page_Load(ByVal sender As Object, ByVal e As EventArgs)
' Create a new GridView object.
Dim customersGridView As New GridView()
' Set the GridView object's properties.
customersGridView.ID = "CustomersGridView"
customersGridView.DataSourceID = "CustomersSource"
customersGridView.AutoGenerateColumns = False
' Dynamically create the columns for the GridView control.
Dim addColumn As New ButtonField()
addColumn.CommandName = "Add"
addColumn.Text = "Add"
addColumn.ButtonType = ButtonType.Link
Dim companyNameColumn As New BoundField()
companyNameColumn.DataField = "CompanyName"
companyNameColumn.HeaderText = "Company Name"
Dim cityColumn As New BoundField()
cityColumn.DataField = "City"
cityColumn.HeaderText = "City"
' Add the columns to the Columns collection
' of the GridView control.
customersGridView.Columns.Add(addColumn)
customersGridView.Columns.Add(companyNameColumn)
customersGridView.Columns.Add(cityColumn)
' Programmatically register the event handling methods.
AddHandler customersGridView.RowCommand, AddressOf CustomersGridView_RowCommand
AddHandler customersGridView.RowCreated, AddressOf CustomersGridView_RowCreated
' Add the GridView object to the Controls collection
' of the PlaceHolder control.
GridViewPlaceHolder.Controls.Add(customersGridView)
End Sub
Sub CustomersGridView_RowCommand(ByVal sender As Object, ByVal e As GridViewCommandEventArgs)
' If multiple ButtonField columns are used, use the
' CommandName property to determine which button was clicked.
If e.CommandName = "Add" Then
' Convert the row index stored in the CommandArgument
' property to an Integer.
Dim index As Integer = Convert.ToInt32(e.CommandArgument)
' Retrieve the row that contains the button clicked
' by the user from the Rows collection. Use the
' CommandSource property to access the GridView control.
Dim customersGridView As GridView = CType(e.CommandSource, GridView)
Dim row As GridViewRow = customersGridView.Rows(index)
' Create a new ListItem object for the customer in the row.
Dim item As New ListItem()
item.Text = Server.HtmlDecode(row.Cells(1).Text) + " " + Server.HtmlDecode(row.Cells(2).Text)
' If the author is not already in the ListBox, add the ListItem
' object to the Items collection of a ListBox control.
If Not CustomersListBox.Items.Contains(item) Then
CustomersListBox.Items.Add(item)
End If
End If
End Sub
Sub CustomersGridView_RowCreated(ByVal sender As Object, ByVal e As GridViewRowEventArgs)
' The GridViewCommandEventArgs class does not contain a
' property that indicates which row's command button was
' clicked. To identify which row was clicked, use the button's
' CommandArgument property by setting it to the row's index.
If e.Row.RowType = DataControlRowType.DataRow Then
' Retrieve the LinkButton control from the first column.
Dim addButton As LinkButton = CType(e.Row.Cells(0).Controls(0), LinkButton)
' Set the LinkButton's CommandArgument property with the
' row's index.
addButton.CommandArgument = e.Row.RowIndex.ToString()
End If
End Sub
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>GridViewCommandEventHandler Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>GridViewCommandEventHandler Example</h3>
<table width="100%">
<tr>
<td style="width:50%">
<asp:placeholder id="GridViewPlaceHolder"
runat="Server"/>
</td>
<td style="vertical-align:top; width:50%">
Customers: <br/>
<asp:listbox id="CustomersListBox"
runat="server"/>
</td>
</tr>
</table>
<!-- 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="CustomersSource"
selectcommand="Select [CustomerID], [CompanyName], [City] From [Customers]"
connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>"
runat="server"/>
</form>
</body>
</html>
I följande exempel visas hur du deklarativt lägger till ett GridViewCommandEventHandler ombud i RowCommand händelsen för en GridView kontroll.
<%@ 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 ContactsGridView_RowCommand(Object sender, GridViewCommandEventArgs e)
{
// If multiple buttons are used in a GridView control, use the
// CommandName property to determine which button was clicked.
if(e.CommandName=="Add")
{
// Convert the row index stored in the CommandArgument
// property to an Integer.
int index = Convert.ToInt32(e.CommandArgument);
// Retrieve the row that contains the button clicked
// by the user from the Rows collection.
GridViewRow row = ContactsGridView.Rows[index];
// Create a new ListItem object for the contact in the row.
ListItem item = new ListItem();
item.Text = Server.HtmlDecode(row.Cells[2].Text) + " " +
Server.HtmlDecode(row.Cells[3].Text);
// If the contact is not already in the ListBox, add the ListItem
// object to the Items collection of the ListBox control.
if (!ContactsListBox.Items.Contains(item))
{
ContactsListBox.Items.Add(item);
}
}
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>GridView RowCommand Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>GridView RowCommand Example</h3>
<table width="100%">
<tr>
<td style="width:50%">
<asp:gridview id="ContactsGridView"
datasourceid="ContactsSource"
allowpaging="true"
autogeneratecolumns="false"
onrowcommand="ContactsGridView_RowCommand"
runat="server">
<columns>
<asp:buttonfield buttontype="Link"
commandname="Add"
text="Add"/>
<asp:boundfield datafield="ContactID"
headertext="Contact ID"/>
<asp:boundfield datafield="FirstName"
headertext="First Name"/>
<asp:boundfield datafield="LastName"
headertext="Last Name"/>
</columns>
</asp:gridview>
</td>
<td style="vertical-align:top; width:50%">
Contacts: <br/>
<asp:listbox id="ContactsListBox"
runat="server" Height="200px" Width="200px"/>
</td>
</tr>
</table>
<!-- This example uses Microsoft SQL Server and connects -->
<!-- to the AdventureWorks sample database. Use an ASP.NET -->
<!-- expression to retrieve the connection string value -->
<!-- from the Web.config file. -->
<asp:sqldatasource id="ContactsSource"
selectcommand="Select [ContactID], [FirstName], [LastName] From Person.Contact"
connectionstring="<%$ ConnectionStrings:AdventureWorks_DataConnectionString%>"
runat="server"/>
</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 ContactsGridView_RowCommand(ByVal sender As Object, ByVal e As GridViewCommandEventArgs)
' If multiple buttons are used in a GridView control, use the
' CommandName property to determine which button was clicked.
If e.CommandName = "Add" Then
' Convert the row index stored in the CommandArgument
' property to an Integer.
Dim index As Integer = Convert.ToInt32(e.CommandArgument)
' Retrieve the row that contains the button clicked
' by the user from the Rows collection.
Dim row As GridViewRow = ContactsGridView.Rows(index)
' Create a new ListItem object for the contact in the row.
Dim item As New ListItem()
item.Text = Server.HtmlDecode(row.Cells(2).Text) & " " & _
Server.HtmlDecode(row.Cells(3).Text)
' If the contact is not already in the ListBox, add the ListItem
' object to the Items collection of the ListBox control.
If Not ContactsListBox.Items.Contains(item) Then
ContactsListBox.Items.Add(item)
End If
End If
End Sub
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head id="Head1" runat="server">
<title>GridView RowCommand Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>GridView RowCommand Example</h3>
<table width="100%">
<tr>
<td style="width:50%">
<asp:gridview id="ContactsGridView"
datasourceid="ContactsSource"
allowpaging="true"
autogeneratecolumns="false"
onrowcommand="ContactsGridView_RowCommand"
runat="server">
<columns>
<asp:buttonfield buttontype="Link"
commandname="Add"
text="Add"/>
<asp:boundfield datafield="ContactID"
headertext="Contact ID"/>
<asp:boundfield datafield="FirstName"
headertext="First Name"/>
<asp:boundfield datafield="LastName"
headertext="Last Name"/>
</columns>
</asp:gridview>
</td>
<td style="vertical-align:top; width:50%">
Contacts: <br/>
<asp:listbox id="ContactsListBox"
runat="server" Height="200px" Width="200px"/>
</td>
</tr>
</table>
<!-- This example uses Microsoft SQL Server and connects -->
<!-- to the AdventureWorks sample database. Use an ASP.NET -->
<!-- expression to retrieve the connection string value -->
<!-- from the Web.config file. -->
<asp:sqldatasource id="ContactsSource"
selectcommand="Select [ContactID], [FirstName], [LastName] From Person.Contact"
connectionstring="<%$ ConnectionStrings:AdventureWorks_DataConnectionString%>"
runat="server"/>
</form>
</body>
</html>
Kommentarer
Händelsen RowCommand aktiveras när en knapp i GridView kontrollen klickas. På så sätt kan du ange en metod för händelsehantering som utför en anpassad rutin när den här händelsen inträffar.
Note
Kontrollen GridView genererar även andra specialiserade händelser när vissa knappar klickas (knappar med CommandName egenskapen inställd på "Ta bort", "Uppdatera" och "Sida" till exempel). När du använder någon av dessa knappar bör du överväga att hantera en av de särskilda händelser som tillhandahålls av kontrollen (till exempel RowDeleted eller RowDeleting).
När du skapar ett GridViewCommandEventHandler ombud identifierar du den metod som ska hantera händelsen. Om du vill associera händelsen med händelsehanteraren lägger du till en instans av ombudet till händelsen. Händelsehanteraren anropas när händelsen inträffar, såvida du inte tar bort ombudet. Mer information om ombud för händelsehanterare finns i Hantera och höja händelser.
Tilläggsmetoder
| Name | Description |
|---|---|
| GetMethodInfo(Delegate) |
Hämtar ett objekt som representerar den metod som representeras av det angivna ombudet. |
