FormView.ItemInserting Olay

Tanım

Bir denetim içindeki FormView Ekle düğmesine tıklandığında, ancak ekleme işleminden önce gerçekleşir.

public:
 event System::Web::UI::WebControls::FormViewInsertEventHandler ^ ItemInserting;
public event System.Web.UI.WebControls.FormViewInsertEventHandler ItemInserting;
member this.ItemInserting : System.Web.UI.WebControls.FormViewInsertEventHandler 
Public Custom Event ItemInserting As FormViewInsertEventHandler 

Olay Türü

Örnekler

Aşağıdaki örnekte, ekleme işlemini iptal etmek için olayının ItemInserting nasıl kullanılacağı gösterilmektedir.


<%@ 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 EmployeeFormView_ItemInserting(Object sender, FormViewInsertEventArgs e)
  {

    MessageLabel.Text = "";

    // Iterate through the items in the Values collection
    // and verify that the user entered a value for each 
    // text box displayed in the insert item template. Cancel
    // the insert operation if the user left a text box empty.
    foreach (DictionaryEntry entry in e.Values)
    {
      if (entry.Value.Equals(""))
      {
        // Use the Cancel property to cancel the 
        // insert operation.
        e.Cancel = true;

        MessageLabel.Text += "Please enter a value for the " +
          entry.Key.ToString() + " field.<br/>";

      }
    }
  }

  void EmployeeFormView_ModeChanged(Object sender, EventArgs e)
  {
    // Clear the MessageLabel Label control when the FormView
    // control changes modes.
    MessageLabel.Text = "";
  }

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>FormViewInsertEventArgs Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>FormViewInsertEventArgs Example</h3>
                       
      <asp:formview id="EmployeeFormView"
        datasourceid="EmployeeSource"
        allowpaging="true"
        datakeynames="EmployeeID"
        emptydatatext="No employees found."
        oniteminserting="EmployeeFormView_ItemInserting"
        onmodechanged="EmployeeFormView_ModeChanged"
        runat="server">

        <itemtemplate>
          <table>
            <tr>
              <td rowspan="5">
                <asp:image id="CompanyLogoImage"
                  imageurl="~/Images/Logo.jpg"
                  alternatetext="Company logo"
                  runat="server"/>
              </td>
              <td colspan="2">
                    
              </td>
            </tr>
            <tr>
              <td>
                <b>Name:</b>
              </td>
              <td>
                <%# Eval("FirstName") %> <%# Eval("LastName") %>
              </td>
            </tr>
            <tr>
              <td>
                <b>Title:</b>
              </td>
              <td>
                <%# Eval("Title") %>
              </td>
            </tr>
            <tr>
              <td colspan="2">
                <asp:linkbutton id="NewButton"
                  text="New"
                  commandname="New"
                  runat="server"/> 
              </td>
            </tr>
          </table>       
        </itemtemplate>
        <insertitemtemplate>
          <table>
            <tr>
              <td rowspan="4">
                <asp:image id="CompanyLogoEditImage"
                  imageurl="~/Images/Logo.jpg"
                  alternatetext="Company logo"
                  runat="server"/>
              </td>
              <td colspan="2">
                    
              </td>
            </tr>
            <tr>
              <td>
                <b><asp:Label
                  runat="server" 
                  AssociatedControlID="FirstNameInsertTextBox" 
                  Text="Name" />:</b>
              </td>
              <td>
                <asp:textbox id="FirstNameInsertTextBox"
                  text='<%# Bind("FirstName") %>'
                  runat="server"/>
                <asp:textbox id="LastNameInsertTextBox"
                  text='<%# Bind("LastName") %>'
                  runat="server"/>
              </td>
            </tr>
            <tr>
              <td>
                <b><asp:Label
                  runat="server" 
                  AssociatedControlID="TitleInsertTextBox" 
                  Text="Title" />:</b>
              </td>
              <td>
                <asp:textbox id="TitleInsertTextBox"
                  text='<%# Bind("Title") %>'
                  runat="server"/> 
              </td>
            </tr>
            <tr>
              <td colspan="2">
                <asp:linkbutton id="InsertButton"
                  text="Insert"
                  commandname="Insert"
                  runat="server"/>
                <asp:linkbutton id="CancelButton"
                  text="Cancel"
                  commandname="Cancel"
                  runat="server"/> 
              </td>
            </tr>
          </table>       
        </insertitemtemplate> 
                  
      </asp:formview>
      
      <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="EmployeeSource"
        selectcommand="Select [EmployeeID], [LastName], [FirstName], [Title], [PhotoPath] From [Employees]"
        insertcommand="Insert Into [Employees] ([LastName], [FirstName], [Title]) VALUES (@LastName, @FirstName, @Title)"
        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 EmployeeFormView_ItemInserting(ByVal sender As Object, ByVal e As FormViewInsertEventArgs)

    MessageLabel.Text = ""

    ' Iterate through the items in the Values collection
    ' and verify that the user entered a value for each 
    ' text box displayed in the insert item template. Cancel
    ' the insert operation if the user left a text box empty.
    
    ' In Visual Basic, the DictionaryItem objects contained in 
    ' the Values collection must be copied to an array before
    ' you can iterate through the collection.
    Dim itemArray(e.Values.Count - 1) As DictionaryEntry
    e.Values.CopyTo(itemArray, 0)
    
    Dim entry As DictionaryEntry
    For Each entry In itemArray
    
      If entry.Value.Equals("") Then
      
        ' Use the Cancel property to cancel the 
        ' insert operation.
        e.Cancel = True

        MessageLabel.Text &= "Please enter a value for the " & _
          entry.Key.ToString() & " field.<br/>"
      
      End If
      
    Next
    
  End Sub

  Sub EmployeeFormView_ModeChanged(ByVal sender As Object, ByVal e As EventArgs)
  
    ' Clear the MessageLabel Label control when the FormView
    ' control changes modes.
    MessageLabel.Text = ""
  
  End Sub

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>FormViewInsertEventArgs Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>FormViewInsertEventArgs Example</h3>
                       
      <asp:formview id="EmployeeFormView"
        datasourceid="EmployeeSource"
        allowpaging="true"
        datakeynames="EmployeeID"
        emptydatatext="No employees found."
        oniteminserting="EmployeeFormView_ItemInserting"
        onmodechanged="EmployeeFormView_ModeChanged"
        runat="server">

        <itemtemplate>
          <table>
            <tr>
              <td rowspan="5">
                <asp:image id="CompanyLogoImage"
                  imageurl="~/Images/Logo.jpg"
                  alternatetext="Company logo"
                  runat="server"/>
              </td>
              <td colspan="2">
                    
              </td>
            </tr>
            <tr>
              <td>
                <b>Name:</b>
              </td>
              <td>
                <%# Eval("FirstName") %> <%# Eval("LastName") %>
              </td>
            </tr>
            <tr>
              <td>
                <b>Title:</b>
              </td>
              <td>
                <%# Eval("Title") %>
              </td>
            </tr>
            <tr>
              <td colspan="2">
                <asp:linkbutton id="NewButton"
                  text="New"
                  commandname="New"
                  runat="server"/> 
              </td>
            </tr>
          </table>       
        </itemtemplate>
        <insertitemtemplate>
          <table>
            <tr>
              <td rowspan="4">
                <asp:image id="CompanyLogoEditImage"
                  imageurl="~/Images/Logo.jpg"
                  alternatetext="Company logo"
                  runat="server"/>
              </td>
              <td colspan="2">
                    
              </td>
            </tr>
            <tr>
              <td>
                <b><asp:Label
                  runat="server" 
                  AssociatedControlID="FirstNameInsertTextBox" 
                  Text="Name" />:</b>
              </td>
              <td>
                <asp:textbox id="FirstNameInsertTextBox"
                  text='<%# Bind("FirstName") %>'
                  runat="server"/>
                <asp:textbox id="LastNameInsertTextBox"
                  text='<%# Bind("LastName") %>'
                  runat="server"/>
              </td>
            </tr>
            <tr>
              <td>
                <b><asp:Label
                  runat="server" 
                  AssociatedControlID="TitleInsertTextBox" 
                  Text="Title" />:</b>
              </td>
              <td>
                <asp:textbox id="TitleInsertTextBox"
                  text='<%# Bind("Title") %>'
                  runat="server"/> 
              </td>
            </tr>
            <tr>
              <td colspan="2">
                <asp:linkbutton id="InsertButton"
                  text="Insert"
                  commandname="Insert"
                  runat="server"/>
                <asp:linkbutton id="CancelButton"
                  text="Cancel"
                  commandname="Cancel"
                  runat="server"/> 
              </td>
            </tr>
          </table>       
        </insertitemtemplate> 
                  
      </asp:formview>
      
      <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="EmployeeSource"
        selectcommand="Select [EmployeeID], [LastName], [FirstName], [Title], [PhotoPath] From [Employees]"
        insertcommand="Insert Into [Employees] ([LastName], [FirstName], [Title]) VALUES (@LastName, @FirstName, @Title)"
        connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>" 
        runat="server"/>
            
    </form>
  </body>
</html>

Açıklamalar

Denetim içindeki FormView bir Ekle düğmesine (özelliği "Ekle" olarak ayarlanmış bir düğmeCommandName) tıklandığında, ancak denetim kaydı eklemeden önce FormView olayı tetiklerItemInserting. Bu, bu olay gerçekleştiğinde bir kaydı veri kaynağına eklemeden önce html kodlaması gibi özel bir yordam gerçekleştiren bir olay işleme yöntemi sağlamanıza olanak tanır.

Bir FormViewInsertEventArgs nesne, denetime gönderilen isteğe bağlı bir komut bağımsız değişkeninin değerini belirlemenize ve ekleme işleminin iptal edilmesi gerektiğini belirtmenize FormView olanak tanıyan olay işleme yöntemine geçirilir. Komut bağımsız değişkeni değeri Ekle düğmesinin CommandArgument özelliğine karşılık gelir. CommandArgument Ekle düğmesinin özelliği ayarlandığında, komut bağımsız değişkeninin değerini belirlemek için özelliğini kullanınCommandArgument. Ekleme işlemini iptal etmek için özelliğini olarak trueayarlayınCancel. Özelliğini kullanarak Values yeni kaydın alan değerlerini okuyabilir veya değiştirebilirsiniz.

Olayları işleme hakkında daha fazla bilgi için bkz. Olayları İşleme ve Oluşturma.

Şunlara uygulanır

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