ListView.InsertNewItem(Boolean) Metodo

Definizione

Inserisce il record corrente nell'origine dati.

public:
 virtual void InsertNewItem(bool causesValidation);
public virtual void InsertNewItem (bool causesValidation);
abstract member InsertNewItem : bool -> unit
override this.InsertNewItem : bool -> unit
Public Overridable Sub InsertNewItem (causesValidation As Boolean)

Parametri

causesValidation
Boolean

true per eseguire la convalida della pagina quando viene chiamato questo metodo, altrimenti false.

Eccezioni

Il controllo ListView non include un elemento di inserimento.

-oppure-

L'oggetto DataSourceView associato al controllo ListView è null.

Esempio

Nell'esempio seguente viene illustrato come usare il metodo per inserire a livello di codice il InsertNewItem contenuto dell'elemento insert di un ListView controllo nell'origine dati.

Importante

L'esempio include una casella di testo che accetta l'input dell'utente e rappresenta quindi una potenziale minaccia alla sicurezza. Per impostazione predefinita, le pagine Web ASP.NET verificano che l'input dell'utente non includa script o elementi HTML. Per altre informazioni, vedere Cenni preliminari sugli attacchi tramite script.

<%@ 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">

  protected void InsertButton_Click(object sender, EventArgs e)
  {
    // Clears any existing message.
    MessageLabel.Text = "";
    
    // Use the InsertNewItem method to programmatically insert
    // the current record in the ListView control.
    DepartmentsListView.InsertNewItem(true);
  }

  protected void DepartmentsListView_ItemInserted(object sender, 
    ListViewInsertedEventArgs e)
  {
    // Handles exceptions that might occur
    // during the insert operation.
    if (e.Exception != null)
    {
      if (e.AffectedRows == 0)
      {
        e.KeepInInsertMode = true;
        MessageLabel.Text = "An exception occurred inserting the new department. " +
                            "Please verify your values and try again.";
      }
      else
        MessageLabel.Text = "An exception occurred inserting the new department. " +
                            "Please verify the values in the newly inserted item.";

      e.ExceptionHandled = true;
    }
  }
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head id="Head1" runat="server">
    <title>ListView InsertNewItem Example</title>
  </head>
  <body>
    <form id="form1" runat="server">
        
      <h3>ListView InsertNewItem Example</h3>
      
      <h5>Departments</h5>

      <asp:ListView ID="DepartmentsListView" 
        DataSourceID="DepartmentsDataSource" 
        DataKeyNames="DepartmentID"
        InsertItemPosition="FirstItem"
        OnItemInserted="DepartmentsListView_ItemInserted"
        runat="server" >
        <LayoutTemplate>
          <table runat="server" id="tblDepartments" width="640px" border="1">
            <tr runat="server" id="itemPlaceholder" />
          </table>
        </LayoutTemplate>
        <ItemTemplate>
          <tr runat="server">
            <td>
              <asp:Label ID="NameLabel" runat="Server" Text='<%#Eval("Name") %>' />
            </td>
            <td>
              <asp:Label ID="GroupNameLabel" runat="Server" Text='<%#Eval("GroupName") %>' />
            </td>
          </tr>
        </ItemTemplate>
        <InsertItemTemplate>
          <tr style="background-color:#00BFFF">
            <td>
              <asp:Label runat="server" ID="NameLabel" AssociatedControlID="NameTextBox" 
                Text="Name:" Font-Bold="true"/><br />
              <asp:TextBox ID="NameTextBox" runat="server" Text='<%#Bind("Name") %>' />
            </td>
            <td>
              <asp:Label runat="server" ID="GroupNameLabel" AssociatedControlID="GroupNameTextBox" 
                Text="Group Name:" Font-Bold="true" /><br />
              <asp:TextBox ID="GroupNameTextBox" runat="server" 
                Text='<%#Bind("GroupName") %>' MaxLength="50" />
            </td>
          </tr>
        </InsertItemTemplate>
      </asp:ListView><br />
              
      <asp:Label ID="MessageLabel"
        ForeColor="Red"
        runat="server" /> <br />

      <asp:Button ID="InsertButton"
        Text="Insert new record"
        OnClick="InsertButton_Click"
        runat="server"  />
    
      <!-- This example uses Microsoft SQL Server and connects    -->
      <!-- to the AdventureWorks sample database. Use an ASP.NET  -->
      <!-- expression to retrieve the connection string value     -->
      <!-- from the Web.config file.                              -->            
      <asp:SqlDataSource ID="DepartmentsDataSource" runat="server" 
        ConnectionString="<%$ ConnectionStrings:AdventureWorks_DataConnectionString %>"
        SelectCommand="SELECT DepartmentID, Name, GroupName FROM HumanResources.Department"
        InsertCommand="INSERT INTO HumanResources.Department(Name, GroupName) 
                VALUES (@Name, @GroupName)">
      </asp:SqlDataSource>
      
    </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">

  Protected Sub InsertButton_Click(ByVal sender As Object, _
                                   ByVal e As EventArgs)
    
    ' Clears any existing message.
    MessageLabel.Text = ""
    
    ' Use the InsertNewItem method to programmatically insert
    ' the current record in the ListView control.
    DepartmentsListView.InsertNewItem(True)
    
  End Sub

  Protected Sub DepartmentsListView_ItemInserted(ByVal sender As Object, _
                                                 ByVal e As ListViewInsertedEventArgs)
  
    ' Handles exceptions that might occur
    ' during the insert operation.
    If Not (e.Exception Is Nothing) Then
      If e.AffectedRows = 0 Then
        e.KeepInInsertMode = True
        MessageLabel.Text = "An exception occurred inserting the new department. " & _
              "Please verify your values and try again."
      Else
        MessageLabel.Text = "An exception occurred inserting the new department. " & _
              "Please verify the values in the newly inserted item."
      End If
        
      e.ExceptionHandled = True
    End If

  End Sub
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head id="Head1" runat="server">
    <title>ListView InsertNewItem Example</title>
  </head>
  <body>
    <form id="form1" runat="server">
        
      <h3>ListView InsertNewItem Example</h3>
      
      <h5>Departments</h5>

      <asp:ListView ID="DepartmentsListView" 
        DataSourceID="DepartmentsDataSource" 
        DataKeyNames="DepartmentID"
        InsertItemPosition="FirstItem"
        OnItemInserted="DepartmentsListView_ItemInserted"
        runat="server" >
        <LayoutTemplate>
          <table runat="server" id="tblDepartments" width="640px" border="1">
            <tr runat="server" id="itemPlaceholder" />
          </table>
        </LayoutTemplate>
        <ItemTemplate>
          <tr runat="server">
            <td>
              <asp:Label ID="NameLabel" runat="Server" Text='<%#Eval("Name") %>' />
            </td>
            <td>
              <asp:Label ID="GroupNameLabel" runat="Server" Text='<%#Eval("GroupName") %>' />
            </td>
          </tr>
        </ItemTemplate>
        <InsertItemTemplate>
          <tr style="background-color:#00BFFF">
            <td>
              <asp:Label runat="server" ID="NameLabel" AssociatedControlID="NameTextBox" 
                Text="Name:" Font-Bold="true"/><br />
              <asp:TextBox ID="NameTextBox" runat="server" Text='<%#Bind("Name") %>' />
            </td>
            <td>
              <asp:Label runat="server" ID="GroupNameLabel" AssociatedControlID="GroupNameTextBox" 
                Text="Group Name:" Font-Bold="true" /><br />
              <asp:TextBox ID="GroupNameTextBox" runat="server" 
                Text='<%#Bind("GroupName") %>' MaxLength="50" />
            </td>
          </tr>
        </InsertItemTemplate>
      </asp:ListView><br />
              
      <asp:Label ID="MessageLabel"
        ForeColor="Red"
        runat="server" /> <br />

      <asp:Button ID="InsertButton"
        Text="Insert new record"
        OnClick="InsertButton_Click"
        runat="server"  />
    
      <!-- This example uses Microsoft SQL Server and connects    -->
      <!-- to the AdventureWorks sample database. Use an ASP.NET  -->
      <!-- expression to retrieve the connection string value     -->
      <!-- from the Web.config file.                              -->            
      <asp:SqlDataSource ID="DepartmentsDataSource" runat="server" 
        ConnectionString="<%$ ConnectionStrings:AdventureWorks_DataConnectionString %>"
        SelectCommand="SELECT DepartmentID, Name, GroupName FROM HumanResources.Department"
        InsertCommand="INSERT INTO HumanResources.Department(Name, GroupName) 
                VALUES (@Name, @GroupName)">
      </asp:SqlDataSource>
      
    </form>
  </body>
</html>

Commenti

Utilizzare il InsertNewItem metodo per inserire a livello di codice un elemento nell'origine dati. Questo metodo viene in genere usato per inserire un elemento dall'esterno del ListView controllo, ad esempio da un controllo diverso nella pagina.

Per usare il InsertNewItem metodo, è necessario definire un InsertItemTemplate modello nel ListView controllo. È anche necessario impostare la InsertItemPosition proprietà su un valore diverso da InsertItemPosition.None. Per specificare se la convalida della pagina viene eseguita prima dell'operazione di inserimento, usare il causesValidation parametro .

Questo metodo genera gli ItemInserted eventi e ItemInserting .

Si applica a

Vedi anche