ObjectDataSource.FilterParameters 屬性

參考

定義

命名空間:: System.Web.UI.WebControls

組件:: System.Web.dll

重要

部分資訊涉及發行前產品，在發行之前可能會有大幅修改。 Microsoft 對此處提供的資訊，不做任何明確或隱含的瑕疵擔保。

取得與 FilterExpression 字串中任何參數替代符號關聯的參數集合。

public:
 property System::Web::UI::WebControls::ParameterCollection ^ FilterParameters { System::Web::UI::WebControls::ParameterCollection ^ get(); };

[System.Web.UI.PersistenceMode(System.Web.UI.PersistenceMode.InnerProperty)]
public System.Web.UI.WebControls.ParameterCollection FilterParameters { get; }

[<System.Web.UI.PersistenceMode(System.Web.UI.PersistenceMode.InnerProperty)>]
member this.FilterParameters : System.Web.UI.WebControls.ParameterCollection

Public ReadOnly Property FilterParameters As ParameterCollection

屬性值

ParameterCollection

ParameterCollection，其中所包含的一組參數，與在 FilterExpression 屬性中找到的任何參數預留位置相關聯。

屬性: PersistenceModeAttribute

例外狀況

NotSupportedException

您設定了 FilterExpression 屬性，但 Select() 方法沒有傳回 DataSet 或 DataTable。

範例

本節包含兩個程式碼範例。第一個 ObjectDataSource 程式代碼範例示範如何使用對象來顯示篩選的數據，以從仲介層商務物件擷取數據，以及 GridView 顯示結果的控件。第二個程式代碼範例提供第一個程式代碼範例中使用的仲介層商務物件範例。

下列程式代碼範例示範如何使用控件來顯示篩選的數據 ObjectDataSource ，以從仲介層商務物件擷取數據，以及 GridView 顯示結果的控件。 ObjectDataSource只有當擷取數據的方法擷取數據做為 DataSet 或 DataTable 物件時，控件才能篩選數據。因此， SelectMethod 屬性會識別商業物件方法，以將資料擷取為 DataSet。

程式代碼範例包含 TextBox 控制項、 GridView 控制項、 ObjectDataSource 控制項和 [提交 ] 按鈕。根據預設，會 TextBox 填入其中一個 Northwind Traders 員工的名稱。會顯示 GridView 中名稱 TextBox所識別之員工的相關信息。若要擷取另一位員工的數據，請在 TextBox中輸入員工的完整名稱，然後按兩下 [ 提交 ] 按鈕。

屬性 FilterExpression 會指定表達式，用來篩選屬性所 SelectMethod 擷取的數據。它會使用評估為集合中 FilterParameters 所含參數的參數佔位元。在此範例中，參數佔位元會以單引號系結，因為參數的類型是可能包含空格的字串類型。如果參數的類型是數值或日期類型，則不需要周框引號。 FilterParameters集合包含一個參數，這是FormParameter系結至控件的 TextBox 物件。

重要

您應該驗證從用戶端接收的任何篩選參數值。運行時間只會將參數值取代為篩選表達式，並將它套用至 DataView 方法所 Select 傳回的物件。如果您使用 FilterExpression 屬性做為安全性量值來限制傳回的項目數，則必須在篩選發生之前驗證參數值。

<%@ Register TagPrefix="aspSample" Namespace="Samples.AspNet.CS" Assembly="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">

    protected void ObjectDataSource1_Filtering(object sender, ObjectDataSourceFilteringEventArgs e)
    {
        if (Textbox1.Text == "")
        {
            e.ParameterValues.Clear();
            e.ParameterValues.Add("FullName", "Nancy Davolio");
        }
    }
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head>
    <title>ObjectDataSource - C# Example</title>
  </head>
  <body>
    <form id="Form1" method="post" runat="server">

        <p>Show all users with the following name.</p>

        <asp:textbox id="Textbox1" runat="server" text="Nancy Davolio" />

        <asp:gridview
          id="GridView1"
          runat="server"
          datasourceid="ObjectDataSource1"
          autogeneratecolumns="False">
          <columns>
            <asp:boundfield headertext="ID" datafield="EmpID" />
            <asp:boundfield headertext="Name" datafield="FullName" />
            <asp:boundfield headertext="Street Address" datafield="Address" />
          </columns>
        </asp:gridview>

        <!-- Security Note: The ObjectDataSource uses a FormParameter,
             Security Note: which does not perform validation of input from the client. -->

        <asp:objectdatasource
          id="ObjectDataSource1"
          runat="server"
          selectmethod="GetAllEmployeesAsDataSet"
          typename="Samples.AspNet.CS.EmployeeLogic"
          filterexpression="FullName='{0}'" OnFiltering="ObjectDataSource1_Filtering">
            <filterparameters>
              <asp:formparameter name="FullName" formfield="Textbox1" defaultvalue="Nancy Davolio" />
            </filterparameters>
        </asp:objectdatasource>

        <p><asp:button id="Button1" runat="server" text="Search" /></p>

    </form>
  </body>
</html>

<%@ Register TagPrefix="aspSample" Namespace="Samples.AspNet.VB" Assembly="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">

    Protected Sub ObjectDataSource1_Filtering(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.ObjectDataSourceFilteringEventArgs)
        If Textbox1.Text = "" Then
            e.ParameterValues.Clear()
            e.ParameterValues.Add("FullName", "Nancy Davolio")
        End If
    End Sub
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head>
    <title>ObjectDataSource - VB Example</title>
  </head>
  <body>
    <form id="Form1" method="post" runat="server">

        <p>Show all users with the following name.</p>

        <asp:textbox id="Textbox1" runat="server" text="Nancy Davolio" />

        <asp:gridview
          id="GridView1"
          runat="server"
          datasourceid="ObjectDataSource1"
          autogeneratecolumns="False">
          <columns>
            <asp:boundfield headertext="ID" datafield="EmpID" />
            <asp:boundfield headertext="Name" datafield="FullName" />
            <asp:boundfield headertext="Street Address" datafield="Address" />
          </columns>
        </asp:gridview>

        <!-- Security Note: The ObjectDataSource uses a FormParameter,
             Security Note: which does not perform validation of input from the client. -->

        <asp:objectdatasource
          id="ObjectDataSource1"
          runat="server"
          selectmethod="GetAllEmployeesAsDataSet"
          typename="Samples.AspNet.VB.EmployeeLogic"
          filterexpression="FullName='{0}'" OnFiltering="ObjectDataSource1_Filtering">
            <filterparameters>
              <asp:formparameter name="FullName" formfield="Textbox1" defaultvalue="Nancy Davolio" />
            </filterparameters>
        </asp:objectdatasource>

        <p><asp:button id="Button1" runat="server" text="Search" /></p>

    </form>
  </body>
</html>

下列程式代碼範例提供上述程式代碼範例所使用的仲介層商務物件範例。程式代碼範例包含兩個基本類別：

類別 EmployeeLogic ，這是封裝商業規則的類別。
類別 NorthwindEmployee ，這是一個模型類別，其中包含從數據層載入和保存數據所需的基本功能。

為了簡單起見，類別 EmployeeLogic 會建立靜態數據集，而不是從數據層擷取數據。此範例也很有幫助，因為此範例依賴您提供 Northwind Traders 員工的完整名稱來示範篩選。如需完整的工作範例，您必須編譯並使用這些類別搭配提供的 Web Forms 程式代碼範例。

namespace Samples.AspNet.CS {

using System;
using System.Collections;
using System.Data;
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 data = new ArrayList();
           
      data.Add(new NorthwindEmployee(1,"Nancy","Davolio","507 - 20th Ave. E. Apt. 2A"));
      data.Add(new NorthwindEmployee(2,"Andrew","Fuller","908 W. Capital Way"));
      data.Add(new NorthwindEmployee(3,"Janet","Leverling","722 Moss Bay Blvd."));
      data.Add(new NorthwindEmployee(4,"Margaret","Peacock","4110 Old Redmond Rd."));
      data.Add(new NorthwindEmployee(5,"Steven","Buchanan","14 Garrett Hill"));
      data.Add(new NorthwindEmployee(6,"Michael","Suyama","Coventry House Miner Rd."));
      data.Add(new NorthwindEmployee(7,"Robert","King","Edgeham Hollow Winchester Way"));
      
      return data;
    }
    
    public static NorthwindEmployee GetEmployee(object anID) {
      ArrayList data = GetAllEmployees() as ArrayList;     
      int empID = Int32.Parse(anID.ToString());      
      return data[empID] as NorthwindEmployee;
    }

    // 
    // To support basic filtering, the employees cannot
    // be returned as an array of objects, rather as a 
    // DataSet of the raw data values. 
    public static DataSet GetAllEmployeesAsDataSet () {
      ICollection employees = GetAllEmployees();
      
      DataSet ds = new DataSet("Table");
      
      // Create the schema of the DataTable.
      DataTable dt = new DataTable();
      DataColumn dc;
      dc = new DataColumn("EmpID",   typeof(int));    dt.Columns.Add(dc);
      dc = new DataColumn("FullName",typeof(string)); dt.Columns.Add(dc);
      dc = new DataColumn("Address", typeof(string)); dt.Columns.Add(dc);
      
      // Add rows to the DataTable.
      DataRow row;
            
      foreach (NorthwindEmployee ne in employees) {                
        row = dt.NewRow();
        row["EmpID"]    = ne.EmpID;
        row["FullName"] = ne.FullName;
        row["Address"]  = ne.Address;
        dt.Rows.Add(row);
      } 
      // Add the complete DataTable to the DataSet.
      ds.Tables.Add(dt);
      
      return ds;
    }    
  }

  public class NorthwindEmployee {

    public NorthwindEmployee (int anID, 
                              string aFirstName,
                              string aLastName,
                              string anAddress) {
      ID = anID;
      firstName = aFirstName;
      lastName = aLastName;   
      address = anAddress;
    }

    private object ID;
    public string EmpID {
      get { return ID.ToString();  }
    }

    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 string FullName {
      get { return FirstName  + " " +  LastName; }
    }
    
    private string address;
    public string Address {
      get { return address; }
      set { address = value;  }
    }    
  }
}

Imports System.Collections
Imports System.Data
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 data As New ArrayList()
      
      data.Add(New NorthwindEmployee(1, "Nancy", "Davolio", "507 - 20th Ave. E. Apt. 2A"))
      data.Add(New NorthwindEmployee(2, "Andrew", "Fuller", "908 W. Capital Way"))
      data.Add(New NorthwindEmployee(3, "Janet", "Leverling", "722 Moss Bay Blvd."))
      data.Add(New NorthwindEmployee(4, "Margaret", "Peacock", "4110 Old Redmond Rd."))
      data.Add(New NorthwindEmployee(5, "Steven", "Buchanan", "14 Garrett Hill"))
      data.Add(New NorthwindEmployee(6, "Michael", "Suyama", "Coventry House Miner Rd."))
      data.Add(New NorthwindEmployee(7, "Robert", "King", "Edgeham Hollow Winchester Way"))
      
      Return data
   End Function 'GetAllEmployees
   
   
   Public Shared Function GetEmployee(anID As Object) As NorthwindEmployee
      Dim data As ArrayList = CType(GetAllEmployees(), ArrayList)
      Dim empID As Integer = Int32.Parse(anID.ToString())
      Return CType(data(empID),NorthwindEmployee)   
   End Function 'GetEmployee
   
   
   ' To support basic filtering, the employees cannot
   ' be returned as an array of objects, rather as a 
   ' DataSet of the raw data values. 
   Public Shared Function GetAllEmployeesAsDataSet() As DataSet
      Dim employees As ICollection = GetAllEmployees()
      
      Dim ds As New DataSet("Table")
      
      ' Create the schema of the DataTable.
      Dim dt As New DataTable()
      Dim dc As DataColumn
      dc = New DataColumn("EmpID", GetType(Integer))
      dt.Columns.Add(dc)
      dc = New DataColumn("FullName", GetType(String))
      dt.Columns.Add(dc)
      dc = New DataColumn("Address", GetType(String))
      dt.Columns.Add(dc)
      
      ' Add rows to the DataTable.
      Dim row As DataRow
      Dim ne As NorthwindEmployee
      For Each ne In employees         
         row = dt.NewRow()
         row("EmpID") = ne.EmpID
         row("FullName") = ne.FullName
         row("Address") = ne.Address
         dt.Rows.Add(row)
      Next
      ' Add the complete DataTable to the DataSet.
      ds.Tables.Add(dt)
      
      Return ds
   End Function 'GetAllEmployeesAsDataSet
      
End Class


Public Class NorthwindEmployee
   
   Public Sub New(anID As Integer, aFirstName As String, aLastName As String, anAddress As String)
      ID = anID
      Me.aFirstName = aFirstName
      Me.aLastName = aLastName
      Me.aAddress = anAddress
   End Sub
   
   Private ID As Object   
   Public ReadOnly Property EmpID() As String
      Get
         Return ID.ToString()
      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 ReadOnly Property FullName() As String
      Get
         Return FirstName & " " & LastName
      End Get
   End Property 
  
   Private aAddress As String  
   Public Property Address() As String
      Get
         Return aAddress
      End Get
      Set
         aAddress = value
      End Set
   End Property 
   
End Class
End Namespace

備註

只有當方法傳DataSet回或 DataTable 物件時，Select控件ObjectDataSource才支援篩選數據。

用於 FilterExpression 的語法是格式字串樣式表示式。篩選表達式語法與屬性接受 Expression 的語法相同。如果您將參數新增至 FilterParameters 集合，您也可以包含格式字串佔位元。例如，在 "{0}" 表達式中包含，以取代參數值。佔位元會根據集合中的 FilterParameters 參數索引來取代。

您可以在屬性中包含 FilterExpression 參數。如果參數是字串或字元類型，請將參數括在單引號中。如果參數是數值類型，則不需要引號。

屬性FilterParameters會FilterParameters擷取與控件相關聯ObjectDataSource之物件所包含的ObjectDataSourceView屬性。

適用於

共用方式為

ObjectDataSource.FilterParameters 屬性

定義

屬性值

例外狀況

範例

備註

適用於

另請參閱

其他資源