DetailsViewRowCollection.Count Eigenschaft
Definition
Wichtig
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Ruft die Anzahl der Elemente im DetailsViewRowCollection-Objekt ab.
public:
property int Count { int get(); };public int Count { get; }member this.Count : intPublic ReadOnly Property Count As IntegerEigenschaftswert
Die Anzahl der Elemente in der DetailsViewRowCollection.
Implementiert
Beispiele
Im folgenden Codebeispiel wird veranschaulicht, wie Sie die Eigenschaft verwenden, um zu ermitteln, ob ein DetailsViewRowCollection Objekt elemente enthält, bevor er durch die Count Auflistung durchlaufen wird.
<%@ 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>
Hinweise
Verwenden Sie die Count Eigenschaft, um die Anzahl der Elemente in der Auflistung zu bestimmen. Die Eigenschaft wird häufig verwendet, wenn sie Count durch die Auflistung durchlaufen wird, um seine obere Grenze zu bestimmen. Die Count Eigenschaft wird auch häufig verwendet, um festzustellen, ob eine Auflistung leer ist.