GridViewCommandEventArgs.CommandSource Vlastnost
Definice
Důležité
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Získá zdroj příkazu.
public:
property System::Object ^ CommandSource { System::Object ^ get(); };public object CommandSource { get; }member this.CommandSource : objPublic ReadOnly Property CommandSource As ObjectHodnota vlastnosti
Instance Object třídy, která představuje zdroj příkazu.
Příklady
Následující příklad ukazuje, jak použít CommandSource vlastnost pro přístup k ovládacímu GridView prvku, který obsahuje tlačítko kliknuto uživatelem.
<%@ 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_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>GridViewCommandEventArgs Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>GridViewCommandEventArgs Example</h3>
<table width="100%">
<tr>
<td style="width:50%">
<asp:gridview id="CustomersGridView"
datasourceid="CustomersSource"
autogeneratecolumns="false"
onrowcommand="CustomersGridView_RowCommand"
onrowcreated="CustomersGridView_RowCreated"
runat="server">
<columns>
<asp:buttonfield buttontype="Link" commandname="Add" text="Add"/>
<asp:boundfield datafield="CompanyName"
headertext="Company Name"/>
<asp:boundfield datafield="City"
headertext="City"/>
</columns>
</asp:gridview>
</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 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>GridViewCommandEventArgs Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>GridViewCommandEventArgs Example</h3>
<table width="100%">
<tr>
<td style="width:50%">
<asp:gridview id="CustomersGridView"
datasourceid="CustomersSource"
autogeneratecolumns="false"
onrowcommand="CustomersGridView_RowCommand"
onrowcreated="CustomersGridView_RowCreated"
runat="server">
<columns>
<asp:buttonfield buttontype="Link" commandname="Add" text="Add"/>
<asp:boundfield datafield="CompanyName"
headertext="Company Name"/>
<asp:boundfield datafield="City"
headertext="City"/>
</columns>
</asp:gridview>
</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>
Poznámky
CommandSource Vlastnost použijte pro přístup k vlastnostem objektu, který představuje zdroj příkazu. V případě GridViewCommandEventArgs objektu je GridView zdrojem příkazu ovládací prvek, který obsahuje tlačítko, na které uživatel kliknul.