DetailsViewRowCollection.Count Eigenschap
Definitie
Belangrijk
Bepaalde informatie heeft betrekking op een voorlopige productversie die aanzienlijk kan worden gewijzigd voordat deze wordt uitgebracht. Microsoft biedt geen enkele expliciete of impliciete garanties met betrekking tot de informatie die hier wordt verstrekt.
Hiermee haalt u het aantal items in het DetailsViewRowCollection object op.
public:
property int Count { int get(); };public int Count { get; }member this.Count : intPublic ReadOnly Property Count As IntegerWaarde van eigenschap
Het aantal items in de DetailsViewRowCollection.
Implementeringen
Voorbeelden
In het volgende codevoorbeeld ziet u hoe u de Count eigenschap gebruikt om te bepalen of een DetailsViewRowCollection object items bevat voordat u de verzameling doorloopt.
<%@ 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 SubmitButton_Click(Object sender, EventArgs e)
{
// Use the Count property to determine whether the
// Rows collection contains any item.
if (ItemDetailsView.Rows.Count > 0)
{
// Iterate through the Rows collection and display
// the value of each field.
MessageLabel.Text = "The row values are: <br/><br/>";
foreach (DetailsViewRow row in ItemDetailsView.Rows)
{
// Use the Text property to access the value of
// each cell. In this example, the cells in the
// first column (index 0) contains the field names,
// while the cells in the second column (index 1)
// contains the field value.
MessageLabel.Text += row.Cells[0].Text + " = " +
row.Cells[1].Text + "<br/>";
}
}
else
{
MessageLabel.Text = "No items.";
}
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>DetailsViewRowCollection Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>DetailsViewRowCollection Example</h3>
<asp:detailsview id="ItemDetailsView"
datasourceid="DetailsViewSource"
allowpaging="true"
autogeneraterows="false"
runat="server">
<fields>
<asp:boundfield datafield="CustomerID"
headertext="Customer ID"/>
<asp:boundfield datafield="CompanyName"
headertext="Company Name"/>
<asp:boundfield datafield="Address"
headertext="Address"/>
<asp:boundfield datafield="City"
headertext="City"/>
<asp:boundfield datafield="PostalCode"
headertext="ZIP Code"/>
<asp:boundfield datafield="Country"
headertext="Country"/>
</fields>
</asp:detailsview>
<br/>
<asp:button id="SubmitButton"
text="Display Row Values"
onclick="SubmitButton_Click"
runat="server"/>
<br/><br/>
<asp:label id="MessageLabel"
forecolor="Red"
runat="server"/>
<!-- 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="DetailsViewSource"
selectcommand="Select [CustomerID], [CompanyName], [Address],
[City], [PostalCode], [Country] 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 SubmitButton_Click(ByVal sender As Object, ByVal e As EventArgs)
' Use the Count property to determine whether the
' Rows collection contains any item.
If ItemDetailsView.Rows.Count > 0 Then
' Iterate through the Rows collection and display
' the value of each field.
MessageLabel.Text = "The row values are: <br/><br/>"
Dim row As DetailsViewRow
For Each row In ItemDetailsView.Rows
' Use the Text property to access the value of
' each cell. In this example, the cells in the
' first column (index 0) contains the field names,
' while the cells in the second column (index 1)
' contains the field value.
MessageLabel.Text &= row.Cells(0).Text & " = " & _
row.Cells(1).Text & "<br/>"
Next
Else
MessageLabel.Text = "No items."
End If
End Sub
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>DetailsViewRowCollection Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>DetailsViewRowCollection Example</h3>
<asp:detailsview id="ItemDetailsView"
datasourceid="DetailsViewSource"
allowpaging="true"
autogeneraterows="false"
runat="server">
<fields>
<asp:boundfield datafield="CustomerID"
headertext="Customer ID"/>
<asp:boundfield datafield="CompanyName"
headertext="Company Name"/>
<asp:boundfield datafield="Address"
headertext="Address"/>
<asp:boundfield datafield="City"
headertext="City"/>
<asp:boundfield datafield="PostalCode"
headertext="ZIP Code"/>
<asp:boundfield datafield="Country"
headertext="Country"/>
</fields>
</asp:detailsview>
<br/>
<asp:button id="SubmitButton"
text="Display Row Values"
onclick="SubmitButton_Click"
runat="server"/>
<br/><br/>
<asp:label id="MessageLabel"
forecolor="Red"
runat="server"/>
<!-- 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="DetailsViewSource"
selectcommand="Select [CustomerID], [CompanyName], [Address],
[City], [PostalCode], [Country] From [Customers]"
connectionstring=
"<%$ ConnectionStrings:NorthWindConnectionString%>"
runat="server"/>
</form>
</body>
</html>
Opmerkingen
Gebruik de Count eigenschap om het aantal items in de verzameling te bepalen. De Count eigenschap wordt vaak gebruikt bij het doorlopen van de verzameling om de bovengrens ervan te bepalen. De Count eigenschap wordt ook vaak gebruikt om te bepalen of een verzameling leeg is.
