DetailsViewRowCollection.Count Egenskap
Definition
Viktigt
En del information gäller för förhandsversionen av en produkt och kan komma att ändras avsevärt innan produkten blir allmänt tillgänglig. Microsoft lämnar inga garantier, uttryckliga eller underförstådda, avseende informationen som visas här.
Hämtar antalet objekt i objektet DetailsViewRowCollection .
public:
property int Count { int get(); };public int Count { get; }member this.Count : intPublic ReadOnly Property Count As IntegerEgenskapsvärde
Antalet objekt i DetailsViewRowCollection.
Implementeringar
Exempel
Följande kodexempel visar hur du använder Count egenskapen för att avgöra om ett DetailsViewRowCollection objekt innehåller några objekt innan det itererar genom samlingen.
<%@ 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>
Kommentarer
Använd egenskapen Count för att fastställa antalet objekt i samlingen. Egenskapen Count används ofta när du itererar genom samlingen för att fastställa dess övre gräns. Egenskapen Count används också ofta för att avgöra om en samling är tom.
