Επεξεργασία

Κοινή χρήση μέσω


FormViewInsertEventArgs Class

Definition

Provides data for the ItemInserting event.

public ref class FormViewInsertEventArgs : System::ComponentModel::CancelEventArgs
public class FormViewInsertEventArgs : System.ComponentModel.CancelEventArgs
type FormViewInsertEventArgs = class
    inherit CancelEventArgs
Public Class FormViewInsertEventArgs
Inherits CancelEventArgs
Inheritance
FormViewInsertEventArgs

Examples

The following example demonstrates how to use the FormViewInsertEventArgs object passed to the event-handling method for the ItemInserting event to cancel an insert operation when the user leaves a field empty.

Important

This example contains a text box that accepts user input, which is a potential security threat. By default, ASP.NET Web pages validate that user input does not include script or HTML elements. For more information, see Script Exploits Overview.


<%@ 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>

Remarks

The FormView control raises the ItemInserting event when an Insert button (a button with its CommandName property set to "Insert") within the control is clicked, but before the FormView control inserts the record. This allows you to provide an event-handling method that performs a custom routine, such as HTML encoding or validating the values of a record before inserting it in the data source, whenever this event occurs.

A FormViewInsertEventArgs object is passed to the event-handling method, which allows you to determine the value of an optional command argument sent to the FormView control and to indicate that the insert operation should be canceled. To determine the value of the command argument, use the CommandArgument property. To cancel the insert operation, set the Cancel property to true. You can also read or modify the field values for the new record by using the Values property.

For more information about how to handle events, see Handling and Raising Events.

For a list of initial property values for an instance of the FormViewInsertEventArgs class, see the FormViewInsertEventArgs constructor.

Constructors

FormViewInsertEventArgs(Object)

Initializes a new instance of the FormViewInsertEventArgs class.

Properties

Cancel

Gets or sets a value indicating whether the event should be canceled.

(Inherited from CancelEventArgs)
CommandArgument

Gets the command argument for the insert operation passed to the FormView control.

Values

Gets a dictionary that contains the field name/value pairs for the record to insert.

Methods

Equals(Object)

Determines whether the specified object is equal to the current object.

(Inherited from Object)
GetHashCode()

Serves as the default hash function.

(Inherited from Object)
GetType()

Gets the Type of the current instance.

(Inherited from Object)
MemberwiseClone()

Creates a shallow copy of the current Object.

(Inherited from Object)
ToString()

Returns a string that represents the current object.

(Inherited from Object)

Applies to

See also