BindingList<T> 类

定义

generic <typename T>
public ref class BindingList : System::Collections::ObjectModel::Collection<T>, System::ComponentModel::IBindingList, System::ComponentModel::ICancelAddNew, System::ComponentModel::IRaiseItemChangedEvents

public class BindingList<T> : System.Collections.ObjectModel.Collection<T>, System.ComponentModel.IBindingList, System.ComponentModel.ICancelAddNew, System.ComponentModel.IRaiseItemChangedEvents

[System.Serializable]
public class BindingList<T> : System.Collections.ObjectModel.Collection<T>, System.ComponentModel.IBindingList, System.ComponentModel.ICancelAddNew, System.ComponentModel.IRaiseItemChangedEvents

type BindingList<'T> = class
    inherit Collection<'T>
    interface ICollection
    interface IEnumerable
    interface IList
    interface IBindingList
    interface ICancelAddNew
    interface IRaiseItemChangedEvents

[<System.Serializable>]
type BindingList<'T> = class
    inherit Collection<'T>
    interface IBindingList
    interface IList
    interface ICollection
    interface IEnumerable
    interface ICancelAddNew
    interface IRaiseItemChangedEvents

Public Class BindingList(Of T)
Inherits Collection(Of T)
Implements IBindingList, ICancelAddNew, IRaiseItemChangedEvents

类型参数

继承

Object

Collection<T>

BindingList<T>

属性

SerializableAttribute

实现

ICollection IEnumerable IList IBindingList ICancelAddNew IRaiseItemChangedEvents

示例

下面的代码示例演示如何绑定到包含业务对象的 BindingList<T> 组件。 这是包含 Main 方法的完整示例。

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Drawing;
using System.Text;
using System.Windows.Forms;

namespace BindingListOfTExamples
{
    public partial class Form1 : Form
    {
        private TextBox textBox2;
        private ListBox listBox1;
        private Button button1;
        private TextBox textBox1;
        Random randomNumber = new Random();
    
        public Form1()
        {
           this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
           this.textBox1 = new System.Windows.Forms.TextBox();
           this.textBox2 = new System.Windows.Forms.TextBox();
           this.listBox1 = new System.Windows.Forms.ListBox();
           this.button1 = new System.Windows.Forms.Button();
           this.textBox1.Location = new System.Drawing.Point(169, 26);
           this.textBox1.Size = new System.Drawing.Size(100, 20);
           this.textBox1.Text = "Bracket";
           this.textBox2.Location = new System.Drawing.Point(169, 57);
           this.textBox2.ReadOnly = true;
           this.textBox2.Size = new System.Drawing.Size(100, 20);
           this.textBox2.Text = "4343";
           this.listBox1.FormattingEnabled = true;
           this.listBox1.Location = new System.Drawing.Point(12, 12);
           this.listBox1.Size = new System.Drawing.Size(120, 95);
           this.button1.Location = new System.Drawing.Point(180, 83);
           this.button1.Size = new System.Drawing.Size(75, 23);
           this.button1.Text = "Add New Item";
           this.button1.Click += new System.EventHandler(this.button1_Click);
           this.ClientSize = new System.Drawing.Size(292, 266);
           this.Controls.Add(this.button1);
           this.Controls.Add(this.listBox1);
           this.Controls.Add(this.textBox2);
           this.Controls.Add(this.textBox1);
           this.Text = "Parts Form";
           this.Load += new EventHandler(Form1_Load);
        }
    
        void Form1_Load(object sender, EventArgs e)
        {
            InitializeListOfParts();
            listBox1.DataSource = listOfParts;
            listBox1.DisplayMember = "PartName";
            listOfParts.AddingNew += new AddingNewEventHandler(listOfParts_AddingNew);
            listOfParts.ListChanged += new ListChangedEventHandler(listOfParts_ListChanged);
        }

        // Declare a new BindingListOfT with the Part business object.
        BindingList<Part> listOfParts; 
        private void InitializeListOfParts()
        {
            // Create the new BindingList of Part type.
            listOfParts = new BindingList<Part>();
    
            // Allow new parts to be added, but not removed once committed.        
            listOfParts.AllowNew = true;
            listOfParts.AllowRemove = false;

            // Raise ListChanged events when new parts are added.
            listOfParts.RaiseListChangedEvents = true;

            // Do not allow parts to be edited.
            listOfParts.AllowEdit = false;
            
            // Add a couple of parts to the list.
            listOfParts.Add(new Part("Widget", 1234));
            listOfParts.Add(new Part("Gadget", 5647));
        }

        // Create a new part from the text in the two text boxes.
        void listOfParts_AddingNew(object sender, AddingNewEventArgs e)
        {
            e.NewObject = new Part(textBox1.Text, int.Parse(textBox2.Text));
        }

        // Add the new part unless the part number contains
        // spaces. In that case cancel the add.
        private void button1_Click(object sender, EventArgs e)
        {
            Part newPart = listOfParts.AddNew();

            if (newPart.PartName.Contains(" "))
            {
                MessageBox.Show("Part names cannot contain spaces.");
                listOfParts.CancelNew(listOfParts.IndexOf(newPart));
            }
            else
            {
                textBox2.Text = randomNumber.Next(9999).ToString();
                textBox1.Text = "Enter part name";
            }
        }

        void listOfParts_ListChanged(object sender, ListChangedEventArgs e)
        {
            MessageBox.Show(e.ListChangedType.ToString());
        }

        [STAThread]
        static void Main()
        {
            Application.EnableVisualStyles();
            Application.Run(new Form1());
        }
    }
    
    // A simple business object for example purposes.
    public class Part
    {
        private string name;
        private int number;
        public Part() { }
        public Part(string nameForPart, int numberForPart)
        {
            PartName = nameForPart;
            PartNumber = numberForPart;
        }

        public string PartName
        {
            get { return name; }
            set { name = value; }
        }

        public int PartNumber
        {
            get { return number; }
            set { number = value; }
        }
    }
}

Option Explicit On
Option Strict On
Imports System.Collections.Generic
Imports System.ComponentModel
Imports System.Drawing
Imports System.Text
Imports System.Windows.Forms

Class Form1
    Inherits Form

    Private textBox2 As TextBox
    Private listBox1 As ListBox
    Private WithEvents button1 As Button
    Private textBox1 As TextBox
    Private randomNumber As New Random()

    Public Sub New()
        Me.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font
        Me.textBox1 = New System.Windows.Forms.TextBox()
        Me.textBox2 = New System.Windows.Forms.TextBox()
        Me.listBox1 = New System.Windows.Forms.ListBox()
        Me.button1 = New System.Windows.Forms.Button()
        Me.textBox1.Location = New System.Drawing.Point(169, 26)
        Me.textBox1.Size = New System.Drawing.Size(100, 20)
        Me.textBox1.Text = "Bracket"
        Me.textBox2.Location = New System.Drawing.Point(169, 57)
        Me.textBox2.ReadOnly = True
        Me.textBox2.Size = New System.Drawing.Size(100, 20)
        Me.textBox2.Text = "4343"
        Me.listBox1.FormattingEnabled = True
        Me.listBox1.Location = New System.Drawing.Point(12, 12)
        Me.listBox1.Size = New System.Drawing.Size(120, 95)
        Me.button1.Location = New System.Drawing.Point(180, 83)
        Me.button1.Size = New System.Drawing.Size(75, 23)
        Me.button1.Text = "Add New Item"
        Me.ClientSize = New System.Drawing.Size(292, 266)
        Me.Controls.Add(Me.button1)
        Me.Controls.Add(Me.listBox1)
        Me.Controls.Add(Me.textBox2)
        Me.Controls.Add(Me.textBox1)
        Me.Text = "Parts Form"
        AddHandler Me.Load, AddressOf Form1_Load

    End Sub

    Sub Form1_Load(ByVal sender As Object, ByVal e As EventArgs)
        InitializeListOfParts()
        listBox1.DataSource = listOfParts
        listBox1.DisplayMember = "PartName"
    End Sub

    ' Declare a new BindingListOfT with the Part business object.
    Private WithEvents listOfParts As BindingList(Of Part)

    Private Sub InitializeListOfParts()

        ' Create the new BindingList of Part type.
        listOfParts = New BindingList(Of Part)

        ' Allow new parts to be added, but not removed once committed.        
        listOfParts.AllowNew = True
        listOfParts.AllowRemove = False

        ' Raise ListChanged events when new parts are added.
        listOfParts.RaiseListChangedEvents = True

        ' Do not allow parts to be edited.
        listOfParts.AllowEdit = False

        ' Add a couple of parts to the list.
        listOfParts.Add(New Part("Widget", 1234))
        listOfParts.Add(New Part("Gadget", 5647))

    End Sub

    ' Create a new part from the text in the two text boxes.
    Private Sub listOfParts_AddingNew(ByVal sender As Object, _
        ByVal e As AddingNewEventArgs) Handles listOfParts.AddingNew
        e.NewObject = New Part(textBox1.Text, Integer.Parse(textBox2.Text))

    End Sub


    ' Add the new part unless the part number contains
    ' spaces. In that case cancel the add.
    Private Sub button1_Click(ByVal sender As Object, _
        ByVal e As EventArgs) Handles button1.Click

        Dim newPart As Part = listOfParts.AddNew()

        If newPart.PartName.Contains(" ") Then
            MessageBox.Show("Part names cannot contain spaces.")
            listOfParts.CancelNew(listOfParts.IndexOf(newPart))
        Else
            textBox2.Text = randomNumber.Next(9999).ToString()
            textBox1.Text = "Enter part name"
        End If

    End Sub

    <STAThread()> _
    Shared Sub Main()
        Application.EnableVisualStyles()
        Application.Run(New Form1())

    End Sub
End Class

' A simple business object for example purposes.
Public Class Part
    Private name As String
    Private number As Integer

    Public Sub New()
    End Sub

    Public Sub New(ByVal nameForPart As String, _
        ByVal numberForPart As Integer)
        PartName = nameForPart
        PartNumber = numberForPart

    End Sub


    Public Property PartName() As String
        Get
            Return name
        End Get
        Set(ByVal value As String)
            name = Value
        End Set
    End Property

    Public Property PartNumber() As Integer
        Get
            Return number
        End Get
        Set(ByVal value As Integer)
            number = Value
        End Set
    End Property
End Class

注解

BindingList<T> 类可用作基类来创建双向数据绑定机制。 BindingList<T> 提供 IBindingList 接口的具体泛型实现。 这是实现完整的 IBindingList 接口的替代方法，由于 IBindingList、IEditableObject和关联的 CurrencyManager之间的细微交互，这一点可能很困难。 但是，典型的解决方案程序员将使用提供数据绑定功能的类，例如 BindingSource，而不是直接使用 BindingList<T>。

BindingList<T> 通过可扩展的 AddNew 方法支持工厂创建的实例。 （在其他类（如 BindingSource）中也发现了这种相同的扩展性类型）此外，由于此类实现 ICancelAddNew 接口，因此它通过 EndNew 和 CancelNew 方法启用新项的事务提交或回滚。

构造函数

属性

方法

事件

显式接口实现

扩展方法

适用于

另请参阅

• IBindingList
• ICancelAddNew
• IEditableObject
• IRaiseItemChangedEvents
• CurrencyManager
• BindingSource