DetailsViewRowCollection.Count Свойство
Определение
Важно!
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Возвращает количество элементов в объекте DetailsViewRowCollection.
public:
property int Count { int get(); };public int Count { get; }member this.Count : intPublic ReadOnly Property Count As IntegerЗначение свойства
Число элементов в объекте DetailsViewRowCollection.
Реализации
Примеры
В следующем примере кода показано, как использовать Count свойство для определения того, содержит ли DetailsViewRowCollection объект какие-либо элементы перед итерациями по коллекции.
<%@ 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>
Комментарии
Count Используйте свойство для определения количества элементов в коллекции. Свойство Count обычно используется при итерации по коллекции, чтобы определить верхнюю границу. Свойство Count также часто используется для определения того, является ли коллекция пустой.