DetailsViewRowCollection.Count Свойство

Определение

Возвращает количество элементов в объекте DetailsViewRowCollection.Gets the number of items in the DetailsViewRowCollection object.

public:
 property int Count { int get(); };
public int Count { get; }
member this.Count : int
Public ReadOnly Property Count As Integer

Значение свойства

Int32

Число элементов в объекте DetailsViewRowCollection.The number of items in the DetailsViewRowCollection.

Реализации

Примеры

В следующем примере кода показано, как использовать Count свойство, чтобы определить, DetailsViewRowCollection содержит ли объект какие-либо элементы перед перебором коллекции.The following code example demonstrates how to use the Count property to determine whether a DetailsViewRowCollection object contains any items before iterating through the collection.


<%@ 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

Используйте Count свойство, чтобы определить количество элементов в коллекции.Use the Count property to determine the number of items in the collection. CountСвойство обычно используется при переборе коллекции для определения ее верхней границы.The Count property is commonly used when iterating through the collection to determine its upper bound. CountСвойство также используется для определения, является ли коллекция пустой.The Count property is also commonly used to determine whether a collection is empty.

Применяется к

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