TableCellCollection.GetEnumerator Metodo

Definizione

Restituisce un oggetto implementato IEnumerator contenente tutti gli oggetti TableCell presenti nella classe TableCellCollection.Returns a IEnumerator implemented object that contains all TableCell objects in the TableCellCollection.

public:
 virtual System::Collections::IEnumerator ^ GetEnumerator();
public System.Collections.IEnumerator GetEnumerator ();
abstract member GetEnumerator : unit -> System.Collections.IEnumerator
override this.GetEnumerator : unit -> System.Collections.IEnumerator
Public Function GetEnumerator () As IEnumerator

Restituisce

Un oggetto implementato IEnumerator che contiene tutti gli oggetti TableCell all'interno di TableCellCollection.A IEnumerator implemented object that contains all TableCell objects within the TableCellCollection.

Implementazioni

Esempi

Nell'esempio seguente viene illustrato come utilizzare il GetEnumerator metodo per creare un System.Collections.IEnumerator oggetto implementato.The following example demonstrates how to use the GetEnumerator method to create a System.Collections.IEnumerator implemented object. Viene quindi iterato per visualizzare gli elementi nella riga selezionata.It is then iterated through to display the items in the selected row.

<%@ 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 Page_Load(Object sender, EventArgs e)
    {

        int numrows = 5;
        int numcells = 6;
        int counter = 1;
        ArrayList a_row = new ArrayList();

        // Create a table.
        for (int rowNum = 0; rowNum < numrows; rowNum++)
        {
            TableRow rw = new TableRow();
            for (int cellNum = 0; cellNum < numcells; cellNum++)
            {
                TableCell cel = new TableCell();
                cel.Text = counter.ToString();
                rw.Cells.Add(cel);
                counter++;
            }
            Table1.Rows.Add(rw);
        }

        if (!IsPostBack)
        {

            // Create a DropDownList for the number of rows.
            for (int rowNum = 0; rowNum < numrows; rowNum++)
            {
                a_row.Add(rowNum.ToString());
            }

            List1.DataSource = a_row;
            List1.DataBind();

        }
    }

    void Button_Click(object sender, EventArgs e)
    {

        int rowNum = List1.SelectedIndex;
        TableCell current_cell;

        // Create the IEnumerator.
        IEnumerator myEnum = Table1.Rows[rowNum].Cells.GetEnumerator();

        Label1.Text = "The items in the selected row are: ";

        // Iterate through the IEnumerator and display its contents.
        while (myEnum.MoveNext())
        {
            current_cell = (TableCell)myEnum.Current;
            Label1.Text = Label1.Text + " " + current_cell.Text;
        }
    }

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head id="Head1" runat="server">
    <title>Untitled Page</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>

    <h3>TableCellCollection Example</h3>
    <asp:Table id="Table1" runat="server" />
    <br />&nbjsp;<br />
    <p style="text-align:center">
        Select a row:
        <br />&nbjsp;<br />
        Row: <asp:DropDownList id="List1" 
            runat="server"/>

        <br />&nbjsp;<br />
        <asp:Button id="Button1"
             Text="Create IEnumerator"
             OnClick="Button_Click"
             runat="server" />
        <br />&nbjsp;<br />
        <asp:Label id="Label1" runat="server"/>
    </p>

    </div>
    </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 Page_Load(ByVal sender As Object, ByVal e As EventArgs)
        
        Dim numRows As Integer = 5
        Dim numCells As Integer = 6
        Dim counter As Integer = 1
        Dim a_row As New ArrayList()
        
        ' Create a table.
        Dim rowNum As Integer
        For rowNum = 0 To numRows - 1
            Dim rw As New TableRow()
            Dim cellNum As Integer
            For cellNum = 0 To numCells - 1
                Dim cel As New TableCell()
                cel.Text = counter.ToString()
                rw.Cells.Add(cel)
                counter += 1
            Next
            Table1.Rows.Add(rw)
        Next
        
        If Not IsPostBack Then
            
            ' Create a DropDownList for the number of rows.
            For rowNum = 0 To numRows - 1
                a_row.Add(rowNum.ToString())
            Next
            
            List1.DataSource = a_row
            List1.DataBind()
        End If
    End Sub

    Sub Button_Click(ByVal sender As Object, ByVal e As EventArgs)
        
        Dim row As Integer = List1.SelectedIndex
        Dim current_cell As TableCell
        
        ' Create the IEnumerator.
        Dim myEnum As IEnumerator = Table1.Rows(row).Cells.GetEnumerator()
        
        Label1.Text = "The items in the selected row are: "
        
        ' Iterate through the IEnumerator and display its contents.
        While myEnum.MoveNext()
            current_cell = CType(myEnum.Current, TableCell)
            Label1.Text = Label1.Text & " " & current_cell.Text
        End While
    End Sub

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>Untitled Page</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>

    <h3>TableCellCollection Example</h3>
    <asp:Table id="Table1" runat="server" />
    <br />&nbjsp;<br />
    <p style="text-align:center">
        Select a row:
        <br />&nbjsp;<br />
        Row: <asp:DropDownList id="List1" 
            runat="server"/>

        <br />&nbjsp;<br />
        <asp:Button id="Button1"
             Text="Create IEnumerator"
             OnClick="Button_Click"
             runat="server" />
        <br />&nbjsp;<br />
        <asp:Label id="Label1" runat="server"/>
    </p>

    </div>
    </form>
</body>
</html>

Commenti

Utilizzare questo metodo per creare un System.Collections.IEnumerator oggetto implementato che può essere iterato facilmente per ottenere ogni elemento TableCellCollectionin.Use this method to create a System.Collections.IEnumerator implemented object that can be iterated through easily to get each item in the TableCellCollection.

Utilizzare la IEnumerator.Current proprietà per ottenere l'elemento a cui punta attualmente nella raccolta.Use the IEnumerator.Current property to get the item currently pointed to in the collection.

Utilizzare il IEnumerator.MoveNext metodo per passare all'elemento successivo della raccolta.Use the IEnumerator.MoveNext method to move to the next item in the collection.

Utilizzare il IEnumerator.Reset metodo per spostare nuovamente l'enumeratore nella posizione iniziale.Use the IEnumerator.Reset method to move the enumerator back to the initial position.

Nota

Il IEnumerator.MoveNext metodo deve essere chiamato dopo la creazione System.Collections.IEnumerator di un oggetto implementato o dopo IEnumerator.Reset l'utilizzo del metodo per spostare l'enumeratore nel primo elemento della raccolta.The IEnumerator.MoveNext method must be called after creating a System.Collections.IEnumerator implemented object or after using the IEnumerator.Reset method to move the enumerator to the first item in the collection. In caso contrario, l'elemento rappresentato IEnumerator.Current dalla proprietà non è definito.Otherwise, the item represented by the IEnumerator.Current property is undefined.

Si applica a

Vedi anche