DetailsViewRowCollection.Count プロパティ

  • リファレンス

定義

名前空間:
System.Web.UI.WebControls
アセンブリ:
System.Web.dll

DetailsViewRowCollection オブジェクト内の項目の数を取得します。

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

プロパティ値

Int32

DetailsViewRowCollection 内の項目数。

実装

Count

例

次のコード例では、 プロパティを使用して、コレクションを Count 反復処理する前にオブジェクトに項目が含まれているかどうかを DetailsViewRowCollection 判断する方法を示します。


<%@ 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>

注釈

コレクション内の Count 項目の数を決定するには、 プロパティを使用します。 プロパティは Count 、通常、コレクションを反復処理して上限を決定するときに使用されます。 プロパティは Count 、コレクションが空かどうかを判断するためにも一般的に使用されます。

適用対象

こちらもご覧ください