ObjectDataSource.DeleteParameters Свойство
Определение
Получает коллекцию параметров, содержащую параметры, используемые методом DeleteMethod.Gets the parameters collection that contains the parameters that are used by the DeleteMethod method.
public:
property System::Web::UI::WebControls::ParameterCollection ^ DeleteParameters { System::Web::UI::WebControls::ParameterCollection ^ get(); };[System.Web.UI.PersistenceMode(System.Web.UI.PersistenceMode.InnerProperty)]
public System.Web.UI.WebControls.ParameterCollection DeleteParameters { get; }[<System.Web.UI.PersistenceMode(System.Web.UI.PersistenceMode.InnerProperty)>]
member this.DeleteParameters : System.Web.UI.WebControls.ParameterCollectionPublic ReadOnly Property DeleteParameters As ParameterCollectionЗначение свойства
Коллекция ParameterCollection, содержащая параметры, используемые методом DeleteMethod.A ParameterCollection that contains the parameters used by the DeleteMethod method.
- Атрибуты
Примеры
Этот раздел содержит два примера кода.This section contains two code examples. В первом примере кода показано, как использовать ObjectDataSource объект с бизнес-объектом и GridView элементом управления для удаления данных.The first code example demonstrates how to use an ObjectDataSource object with a business object and a GridView control to delete data. Во втором примере кода показан EmployeeLogic класс, который используется в первом примере кода.The second code example shows the EmployeeLogic class that is used in the first code example.
В следующем примере кода показано, как использовать DeleteParameters свойство ObjectDataSource элемента управления с бизнес-объектом и GridView элементом управления для удаления данных.The following code example demonstrates how to use the DeleteParameters property of the ObjectDataSource control with a business object and a GridView control to delete data. Изначально GridView элемент управления отображает набор всех сотрудников, используя метод, заданный SelectMethod свойством, для получения данных из EmployeeLogic объекта.Initially, the GridView control displays a set of all employees, using the method that is specified by the SelectMethod property to retrieve the data from the EmployeeLogic object. Так как AutoGenerateDeleteButton свойство имеет значение true , GridView элемент управления автоматически отображает кнопку Delete .Because the AutoGenerateDeleteButton property is set to true, the GridView control automatically displays a Delete button.
Если нажать кнопку Удалить , Deleting событие вызывается с двумя параметрами.If you click the Delete button, the Deleting event is called with two parameters. Один параметр, EmpID , поступает из DataGrid элемента управления и основан на DataKeyNames свойстве.One parameter, EmpID, comes from the DataGrid control, and is based on the DataKeyNames property. Другой параметр берется из декларативного DeleteParameters Свойства.The other parameter comes from the declarative DeleteParameters property. EmployeeLogicКласс перегружает DeleteEmployee метод.The EmployeeLogic class overloads the DeleteEmployee method. Одна перегрузка принимает NorthwindEmployee параметр, а другой принимает Int32 параметр с именем anID .One overload takes a NorthwindEmployee parameter, and the other takes an Int32 parameter named anID. В Deleting событии записи в InputParameters свойстве настраиваются так, чтобы включался только один параметр anID с именем и значением из original_EmpID .In the Deleting event, the entries in the InputParameters property are adjusted to include only one parameter named anID with the value from original_EmpID. Если обработчик событий существует, DeleteEmployee вызывается соответствующий метод.When the event handler exists, the matching DeleteEmployee method is called.
В следующем примере кода показана веб-страница, на которой отображается DataGrid элемент управления и обрабатывается Deleting событие.The following code example shows the Web page that displays the DataGrid control and handles the Deleting event.
<%@ Register TagPrefix="aspSample" Namespace="Samples.AspNet.CS" Assembly="Samples.AspNet.CS" %>
<%@ Import namespace="Samples.AspNet.CS" %>
<%@ 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">
private void NorthwindEmployeeDeleting(object source, ObjectDataSourceMethodEventArgs e)
{
IDictionary paramsFromPage = e.InputParameters;
paramsFromPage.Remove("anID");
paramsFromPage.Add("anID", (int)paramsFromPage["EmpID"]);
paramsFromPage.Remove("EmpID");
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head>
<title>ObjectDataSource - C# Example</title>
</head>
<body>
<form id="Form1" method="post" runat="server">
<asp:gridview
id="GridView1"
runat="server"
datasourceid="ObjectDataSource1"
autogeneratedeletebutton="true"
DataKeyNames="EmpID">
</asp:gridview>
<asp:objectdatasource
id="ObjectDataSource1"
runat="server"
selectmethod="GetAllEmployees"
deletemethod="DeleteEmployee"
OnDeleting="NorthwindEmployeeDeleting"
typename="Samples.AspNet.CS.EmployeeLogic">
<deleteparameters>
<asp:parameter name="anID" type="Int32" />
</deleteparameters>
</asp:objectdatasource>
</form>
</body>
</html>
<%@ Register TagPrefix="aspSample" Namespace="Samples.AspNet.VB" Assembly="Samples.AspNet.VB" %>
<%@ Import namespace="Samples.AspNet.VB" %>
<%@ 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">
Private Sub NorthwindEmployeeDeleting(source As Object, e As ObjectDataSourceMethodEventArgs)
Dim paramsFromPage As IDictionary = e.InputParameters
paramsFromPage.Remove("anID")
paramsFromPage.Add("anID", CInt(paramsFromPage("EmpID")))
paramsFromPage.Remove("EmpID")
End Sub ' NorthwindEmployeeDeleting
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head>
<title>ObjectDataSource - VB Example</title>
</head>
<body>
<form id="Form1" method="post" runat="server">
<asp:gridview
id="GridView1"
runat="server"
datasourceid="ObjectDataSource1"
autogeneratedeletebutton="true"
DataKeyNames="EmpID">
</asp:gridview>
<asp:objectdatasource
id="ObjectDataSource1"
runat="server"
selectmethod="GetAllEmployees"
deletemethod="DeleteEmployee"
OnDeleting="NorthwindEmployeeDeleting"
typename="Samples.AspNet.VB.EmployeeLogic">
<deleteparameters>
<asp:parameter name="anID" type="Int32" />
</deleteparameters>
</asp:objectdatasource>
</form>
</body>
</html>
В следующем примере кода показан EmployeeLogic класс, который используется в предыдущем примере кода.The following code example shows the EmployeeLogic class that is used in the preceding code example.
namespace Samples.AspNet.CS {
using System;
using System.Collections;
using System.Configuration;
using System.Data;
using System.Data.SqlClient;
using System.Web.UI;
using System.Web.UI.WebControls;
//
// EmployeeLogic is a stateless business object that encapsulates
// the operations you can perform on a NorthwindEmployee object.
//
public class EmployeeLogic {
// Returns a collection of NorthwindEmployee objects.
public static ICollection GetAllEmployees () {
ArrayList al = new ArrayList();
// Use the SqlDataSource class to wrap the
// ADO.NET code required to query the database.
ConnectionStringSettings cts = ConfigurationManager.ConnectionStrings["NorthwindConnection"];
SqlDataSource sds
= new SqlDataSource(cts.ConnectionString,
"SELECT EmployeeID FROM Employees");
try {
IEnumerable IDs = sds.Select(DataSourceSelectArguments.Empty);
// Iterate through the Enumeration and create a
// NorthwindEmployee object for each ID.
IEnumerator enumerator = IDs.GetEnumerator();
while (enumerator.MoveNext()) {
// The IEnumerable contains DataRowView objects.
DataRowView row = enumerator.Current as DataRowView;
int id = (int) row["EmployeeID"];
NorthwindEmployee nwe = new NorthwindEmployee(id);
// Add the NorthwindEmployee object to the collection.
al.Add(nwe);
}
}
finally {
// If anything strange happens, clean up.
sds.Dispose();
}
return al;
}
public static NorthwindEmployee GetEmployee(int anID) {
return new NorthwindEmployee(anID);
}
public static void DeleteEmployee(NorthwindEmployee ne) {
bool retval = ne.Delete();
if (! retval) { throw new NorthwindDataException("Employee delete failed."); }
// Delete the object in memory.
ne = null;
}
public static void DeleteEmployee(int anID) {
NorthwindEmployee tempEmp = new NorthwindEmployee(anID);
DeleteEmployee(tempEmp);
}
}
public class NorthwindEmployee {
public NorthwindEmployee (int anID) {
this.ID = anID;
ConnectionStringSettings cts = ConfigurationManager.ConnectionStrings["NorthwindConnection"];
SqlConnection conn = new SqlConnection (cts.ConnectionString);
SqlCommand sc =
new SqlCommand(" SELECT FirstName,LastName " +
" FROM Employees " +
" WHERE EmployeeID = @empId",
conn);
// Add the employee ID parameter and set its value.
sc.Parameters.Add(new SqlParameter("@empId",SqlDbType.Int)).Value = Int32.Parse(anID.ToString());
SqlDataReader sdr = null;
try {
conn.Open();
sdr = sc.ExecuteReader();
// This is not a while loop. It only loops once.
if (sdr != null && sdr.Read()) {
// The IEnumerable contains DataRowView objects.
this.firstName = sdr["FirstName"].ToString();
this.lastName = sdr["LastName"].ToString();
}
else {
throw new NorthwindDataException("Data not loaded for employee id.");
}
}
finally {
try {
if (sdr != null) sdr.Close();
conn.Close();
}
catch (SqlException) {
// Log an event in the Application Event Log.
throw;
}
}
}
private object ID;
public object EmpID {
get { return ID; }
}
private string lastName;
public string LastName {
get { return lastName; }
set { lastName = value; }
}
private string firstName;
public string FirstName {
get { return firstName; }
set { firstName = value; }
}
public bool Delete () {
if (ID.Equals(DBNull.Value)) {
// The Employee object is not persisted.
return true;
}
else {
// The Employee object is persisted.
// Use the SqlDataSource control as a convenient wrapper for
// the ADO.NET code needed to delete a record from the database.
ConnectionStringSettings cts = ConfigurationManager.ConnectionStrings["NorthwindConnection"];
SqlDataSource sds = new SqlDataSource();
try {
sds.ConnectionString = cts.ConnectionString;
sds.DeleteCommand = "DELETE FROM Employees WHERE EmployeeID=@empID;";
sds.DeleteParameters.Add(new Parameter("empID",TypeCode.Int32,this.ID.ToString()));
/* To make this sample fully functional, uncomment these lines
int retval = sds.Delete();
if (retval == 1) { return true; }
return false; */
return true;
}
finally {
sds.Dispose();
}
}
}
}
internal class NorthwindDataException: Exception {
public NorthwindDataException(string msg) : base (msg) { }
}
}
Imports System.Collections
Imports System.Configuration
Imports System.Data
Imports System.Data.SqlClient
Imports System.Web.UI
Imports System.Web.UI.WebControls
Namespace Samples.AspNet.VB
'
' EmployeeLogic is a stateless business object that encapsulates
' the operations you can perform on a NorthwindEmployee object.
Public Class EmployeeLogic
' Returns a collection of NorthwindEmployee objects.
Public Shared Function GetAllEmployees() As ICollection
Dim al As New ArrayList()
' Use the SqlDataSource class to wrap the
' ADO.NET code required to query the database.
Dim cts As ConnectionStringSettings = ConfigurationManager.ConnectionStrings("NorthwindConnection")
Dim sds As New SqlDataSource(cts.ConnectionString, "SELECT EmployeeID FROM Employees")
Try
Dim IDs As IEnumerable = sds.Select(DataSourceSelectArguments.Empty)
' Iterate through the Enumeration and create a
' NorthwindEmployee object for each ID.
Dim enumerator As IEnumerator = IDs.GetEnumerator()
While enumerator.MoveNext()
' The IEnumerable contains DataRowView objects.
Dim row As DataRowView = CType(enumerator.Current,DataRowView)
Dim id As String = row("EmployeeID").ToString()
Dim nwe As New NorthwindEmployee(CInt(id))
' Add the NorthwindEmployee object to the collection.
al.Add(nwe)
End While
Finally
' If anything strange happens, clean up.
sds.Dispose()
End Try
Return al
End Function 'GetAllEmployees
Public Shared Function GetEmployee(anID As Integer) As NorthwindEmployee
Return New NorthwindEmployee(anID)
End Function 'GetEmployee
Public Shared Sub DeleteEmployee(ne As NorthwindEmployee)
Dim retval As Boolean = ne.Delete()
If Not retval Then
Throw New NorthwindDataException("Employee delete failed.")
End If ' Delete the object in memory.
ne = Nothing
End Sub
Public Shared Sub DeleteEmployee(anID As Integer)
Dim tempEmp As New NorthwindEmployee(anID)
DeleteEmployee(tempEmp)
End Sub
' And so on...
End Class
Public Class NorthwindEmployee
Public Sub New(anID As Integer)
Me.ID = anID
Dim cts As ConnectionStringSettings = ConfigurationManager.ConnectionStrings("NorthwindConnection")
Dim conn As New SqlConnection(cts.ConnectionString)
Dim sc As New SqlCommand(" SELECT FirstName,LastName " & _
" FROM Employees " & _
" WHERE EmployeeID = @empId", conn)
' Add the employee ID parameter and set its value.
sc.Parameters.Add(New SqlParameter("@empId", SqlDbType.Int)).Value = Int32.Parse(anID.ToString())
Dim sdr As SqlDataReader = Nothing
Try
conn.Open()
sdr = sc.ExecuteReader()
' This is not a while loop. It only loops once.
If Not (sdr Is Nothing) AndAlso sdr.Read() Then
' The IEnumerable contains DataRowView objects.
Me.firstName = sdr("FirstName").ToString()
Me.lastName = sdr("LastName").ToString()
Else
Throw New NorthwindDataException("Data not loaded for employee id.")
End If
Finally
Try
If Not (sdr Is Nothing) Then
sdr.Close()
End If
conn.Close()
Catch se As SqlException
' Log an event in the Application Event Log.
Throw
End Try
End Try
End Sub
Private ID As Object
Public ReadOnly Property EmpID() As Object
Get
Return ID
End Get
End Property
Private aLastName As String
Public Property LastName() As String
Get
Return aLastName
End Get
Set
aLastName = value
End Set
End Property
Private aFirstName As String
Public Property FirstName() As String
Get
Return aFirstName
End Get
Set
aFirstName = value
End Set
End Property
Public Function Delete() As Boolean
If ID.Equals(DBNull.Value) Then
' The Employee object is not persisted.
Return True
Else
' The Employee object is persisted.
' Use the SqlDataSource control as a convenient wrapper for
' the ADO.NET code needed to delete a record from the database.
Dim cts As ConnectionStringSettings = ConfigurationManager.ConnectionStrings("NorthwindConnection")
Dim sds As New SqlDataSource()
Try
sds.ConnectionString = cts.ConnectionString
sds.DeleteCommand = "DELETE FROM Employees WHERE EmployeeID=@empID;"
Dim param As New Parameter("empID", TypeCode.Int32, CStr(Me.ID))
sds.DeleteParameters.Add(param)
' To make this sample fully functional, uncomment these lines
' int retval = sds.Delete();
' if (retval == 1) { return true; }
' return false;
Return True
Finally
sds.Dispose()
End Try
End If
End Function 'Delete
End Class
Friend Class NorthwindDataException
Inherits Exception
Public Sub New(msg As String)
MyBase.New(msg)
End Sub
End Class
End Namespace
Комментарии
Имена и типы параметров, содержащихся в DeleteParameters коллекции, должны соответствовать именам и типам параметров в DeleteMethod сигнатуре метода.The names and types of the parameters that are contained in the DeleteParameters collection must match the names and types of the parameters in the DeleteMethod method signature. На имена параметров зависят OldValuesParameterFormatString Свойства и учитывается регистр.The parameter names are affected by the OldValuesParameterFormatString property and are case-sensitive. Параметры в коллекции зависят от данных, находящихся в элементе управления с привязкой к данным, параметров, которые декларативно задаются, и параметров, которые добавляются программно.The parameters in the collection depend on the data that is in the data-bound control, the parameters that are specified declaratively, and the parameters that are added programmatically. Дополнительные сведения см. в разделе "объединение параметров" раздела Delete и Использование параметров с элементом управления ObjectDataSource.For more information, see "Parameter Merging" in Delete and Using Parameters with the ObjectDataSource Control.
DeleteParametersСвойство получает DeleteParameters свойство, содержащееся в ObjectDataSourceView объекте, связанном с ObjectDataSource элементом управления.The DeleteParameters property retrieves the DeleteParameters property that is contained by the ObjectDataSourceView object that is associated with the ObjectDataSource control.
Дополнительные сведения о слиянии параметров, времени существования объектов и разрешении методов см. в разделе DeleteMethod .For more information about parameter merging, object lifetime, and method resolution, see DeleteMethod.
Применяется к
См. также раздел
- DeleteMethod
- Delete()
- Элементы управления веб-сервером с источником данныхData Source Web Server Controls
- Общие сведения об элементе управления ObjectDataSourceObjectDataSource Control Overview
- Создание исходного объекта элемента управления ObjectDataSourceCreating an ObjectDataSource Control Source Object