DataControlRowType Enumeração
Definição
Importante
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Especifica a função de uma linha em um controle de dados, como um controle DetailsView ou GridView.
public enum class DataControlRowTypepublic enum DataControlRowTypetype DataControlRowType = Public Enum DataControlRowType- Herança
Campos
| DataRow | 2 | Uma linha de dados de um controle de dados. Somente linhas DataRow podem ser associadas a dados. |
| EmptyDataRow | 5 | A linha vazia de um controle com limite de dados. A linha vazia é exibida quando o controle com limite de dados não tem registros a serem exibidos e o modelo |
| Footer | 1 | Uma linha de rodapé de um controle de dados. Linhas de rodapé não podem ser associadas a dados. |
| Header | 0 | Uma linha de cabeçalho de um controle de dados. Linhas de cabeçalho não podem ser associadas a dados. |
| Pager | 4 | Uma linha que exibe botões de pager ou um controle de paginação. Linhas de pager não podem ser associadas a dados. |
| Separator | 3 | Um separador de linha. Separadores de linha não podem ser associados a dados. |
Exemplos
O exemplo de código a seguir demonstra como usar a DataControlRowType enumeração para verificar o tipo de uma linha ao trabalhar com um GridView controle. O AuthorsGridView_RowCreated método garante que a CommandArgument propriedade de um LinkButton controle seja exclusiva para todas as linhas de dados no GridView controle, para que, quando o controle de LinkButton uma linha for clicado, ele possa ser identificado corretamente.
<%@ 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>GridViewCommandEventArgs Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>GridViewCommandEventArgs 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>GridViewCommandEventArgs Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>GridViewCommandEventArgs 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>
Comentários
A DataControlRowType enumeração identifica a função de linhas em um controle de dados. Ele é usado pelo e GridView pelos DetailsView controles para distinguir entre linhas que exibem dados e linhas que exibem outros elementos de interface do usuário, como uma linha de cabeçalho, separador de linha ou botões de pager.
Você pode usar a DataControlRowType enumeração para identificar o tipo de um GridViewRow objeto ou DetailsViewRow quando enumerar por meio de uma GridViewRowCollection ou DetailsViewRowCollection coleção. Se você estiver escrevendo um controle de dados que cria linhas, poderá usar a DataControlRowType enumeração para identificar a função de diferentes linhas no controle.