Čítať v angličtine Upraviť

Zdieľať cez

DetailsViewCommandEventArgs.CommandSource Property

  • Reference

Definition

Namespace:
System.Web.UI.WebControls
Assembly:
System.Web.dll

Gets the source of the command.

C# 
public object CommandSource { get; }

Property Value

Object

An instance of the Object class that represents the source of the command.

Examples

The following code example demonstrates how to use the CommandSource property to determine which of two DetailsView controls raised the ItemCommand event.

ASP.NET (C#) 
<%@ 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 ItemDetailsView_ItemCommand(Object sender, 
    DetailsViewCommandEventArgs e)
  {

    // Use the CommandName property to determine which button
    // was clicked. 
    if (e.CommandName == "Add")
    {
      
      // Because this event handler is used for two different
      // DetailsView controls, use the CommandSource property 
      // to get the DetailsView control that raised the event.
      DetailsView view = (DetailsView)e.CommandSource;
      
      // Determine which ListBox control to update based on the
      // ID of the DetailsView control that raised the event.
      ListBox list;
      if (view.ID == "CustomerDetailsView")
      {
        list = CustomerListBox;
      }
      else
      {
        list = EmployeesListBox;
      }

      // Add the selected item to the appropriate ListBox control. 

      // Get the row that contains the value to add. For this
      // example, get the second row (index 1) of the DetailsView 
      // control.
      DetailsViewRow row = view.Rows[1];

      // Get the value from the appropriate cell. For this
      // example, get the value of the second cell (index 1) 
      // of the row.
      String value = row.Cells[1].Text;

      // Create a ListItem object using the value.
      ListItem item = new ListItem(value);

      // Add the ListItem object to the ListBox control, if the 
      // item does not already exist.
      if (!list.Items.Contains(item))
      {
        list.Items.Add(item);
      }

    }

  }
  
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>DetailsViewCommandEventArgs CommandSource Example</title>
</head>
<body>
    <form id="form1" runat="server">
    
      <h3>DetailsViewCommandEventArgs CommandSource Example</h3>
  
      <table border="0">
        <tr valign="top">
          <td>
            <asp:detailsview id="CustomerDetailsView"
              datasourceid="CustomerSource"
              allowpaging="true"
              autogeneraterows="true" 
              onitemcommand="ItemDetailsView_ItemCommand"  
              runat="server">
              <fields>
                <asp:buttonfield buttontype="Link"
                  causesvalidation="false"
                  text="Add to List"
                  commandname="Add"/>
              </fields>
            </asp:detailsview>
          </td>
          <td>
            <asp:detailsview id="EmployeesDetailsView"
              datasourceid="EmployeesSource"
              allowpaging="true"
              autogeneraterows="true" 
              onitemcommand="ItemDetailsView_ItemCommand"  
              runat="server">
              <fields>
                <asp:buttonfield buttontype="Link"
                  causesvalidation="false"
                  text="Add to List"
                  commandname="Add"/>
              </fields>
            </asp:detailsview>
          </td>
        </tr>
        <tr>
          <td>
            Selected Customers:<br/>
            <asp:listbox id="CustomerListBox"
              runat="server"/>
          </td>
          <td>
            Selected Employees:<br/>
            <asp:listbox id="EmployeesListBox"
              runat="server"/>
          </td>
        </tr>
      </table>
      
      <!-- 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="CustomerSource"
        selectcommand="Select [CustomerID], [CompanyName], [Address], 
          [City], [PostalCode], [Country] From [Customers]"
        connectionstring=
            "<%$ ConnectionStrings:NorthWindConnectionString%>" 
        runat="server"/>  
        
      <asp:sqldatasource id="EmployeesSource"
        selectcommand="Select [EmployeeID], [FirstName], [LastName], 
          [Title] From [Employees]"
        connectionstring=
            "<%$ ConnectionStrings:NorthWindConnectionString%>" 
        runat="server"/>
  
    </form>
  </body>
</html>

Remarks

Use the CommandSource property to access the properties of the object that represents the source of the command. In some cases, this will be the DetailsView control itself, and in other cases it will be the Button control that was clicked.

Applies to

Produkt Verzie
.NET Framework 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1

See also