如何:访问绑定到 Windows 窗体 DataGridView 行的对象

有时,显示业务对象集合中存储的信息的表很有用。 将 DataGridView 控件绑定到此类集合时,每个公共属性都将在它自己的列中显示,除非该属性已用 BrowsableAttribute 标记为不可浏览。 例如,Customer 对象的集合将具有如**“姓名”“地址”**等列。

如果这些对象包含您希望访问的附加信息和代码,则可以通过行对象来实现。 在下面的代码示例中,用户可以选择多行并单击一个按钮将发票发送给每个对应客户。

访问行绑定对象

  • 使用 DataGridViewRow.DataBoundItem 属性。

    Private Sub InvoiceButton_Click(ByVal sender As System.Object, _
        ByVal e As System.EventArgs) Handles InvoiceButton.Click
    
        For Each row As DataGridViewRow In Me.DataGridView1.SelectedRows
    
            Dim cust As Customer = TryCast(row.DataBoundItem, Customer)
            If cust IsNot Nothing Then
                cust.SendInvoice()
            End If
    
        Next
    
    End Sub
    
    void invoiceButton_Click(object sender, EventArgs e)
    {
        foreach (DataGridViewRow row in this.dataGridView1.SelectedRows)
        {
            Customer cust = row.DataBoundItem as Customer;
            if (cust != null)
            {
                cust.SendInvoice();
            }
        }
    }
    

示例

完整的代码示例包括一个简单的 Customer 实现,并将 DataGridView 绑定到一个包含几个 Customer 对象的 ArrayList。 因为在 Form.Load 事件处理程序之外无法访问客户集合,所以 System.Windows.Forms.ButtonClick 事件处理程序必须通过行访问 Customer 对象。

Imports System
Imports System.Windows.Forms

Public Class DataGridViewObjectBinding
    Inherits Form

    ' These declarations and the Main() and New() methods 
    ' below can be replaced with designer-generated code. 
    Private WithEvents InvoiceButton As New Button()
    Private WithEvents DataGridView1 As New DataGridView()

    ' Entry point code. 
    <STAThreadAttribute()> _
    Public Shared Sub Main()

        Application.Run(New DataGridViewObjectBinding())

    End Sub

    ' Sets up the form. 
    Public Sub New()

        Me.DataGridView1.Dock = DockStyle.Fill
        Me.Controls.Add(Me.DataGridView1)

        Me.InvoiceButton.Text = "invoice the selected customers"
        Me.InvoiceButton.Dock = DockStyle.Top
        Me.Controls.Add(Me.InvoiceButton)
        Me.Text = "DataGridView collection-binding demo"

    End Sub

    Private Sub Form1_Load(ByVal sender As System.Object, _
        ByVal e As System.EventArgs) Handles MyBase.Load

        ' Set up a collection of objects for binding.
        Dim customers As New System.Collections.ArrayList()
        customers.Add(New Customer("Harry"))
        customers.Add(New Customer("Sally"))
        customers.Add(New Customer("Roy"))
        customers.Add(New Customer("Pris"))

        ' Initialize and bind the DataGridView.
        Me.DataGridView1.SelectionMode = _
            DataGridViewSelectionMode.FullRowSelect
        Me.DataGridView1.AutoGenerateColumns = True
        Me.DataGridView1.DataSource = customers

    End Sub

    ' Calls the SendInvoice() method for the Customer 
    ' object bound to each selected row.
    Private Sub InvoiceButton_Click(ByVal sender As System.Object, _
        ByVal e As System.EventArgs) Handles InvoiceButton.Click

        For Each row As DataGridViewRow In Me.DataGridView1.SelectedRows

            Dim cust As Customer = TryCast(row.DataBoundItem, Customer)
            If cust IsNot Nothing Then
                cust.SendInvoice()
            End If

        Next

    End Sub

End Class

Public Class Customer

    Private nameValue As String

    Public Sub New(ByVal name As String)
        nameValue = name
    End Sub

    Public Property Name() As String
        Get
            Return nameValue
        End Get
        Set(ByVal value As String)
            nameValue = value
        End Set
    End Property

    Public Sub SendInvoice()
        MsgBox(nameValue & " has been billed.")
    End Sub

End Class
using System;
using System.Windows.Forms;

public class DataGridViewObjectBinding : Form
{
    // These declarations and the Main() and New() methods 
    // below can be replaced with designer-generated code. 
    private Button invoiceButton = new Button();
    private DataGridView dataGridView1 = new DataGridView();

    // Entry point code. 
    [STAThreadAttribute()]
    public static void Main()
    {
        Application.Run(new DataGridViewObjectBinding());
    }

    // Sets up the form.
    public DataGridViewObjectBinding()
    {
        this.dataGridView1.Dock = DockStyle.Fill;
        this.Controls.Add(this.dataGridView1);

        this.invoiceButton.Text = "invoice the selected customers";
        this.invoiceButton.Dock = DockStyle.Top;
        this.invoiceButton.Click += new EventHandler(invoiceButton_Click);
        this.Controls.Add(this.invoiceButton);

        this.Load += new EventHandler(DataGridViewObjectBinding_Load);
        this.Text = "DataGridView collection-binding demo";
    }

    void  DataGridViewObjectBinding_Load(object sender, EventArgs e)
    {
        // Set up a collection of objects for binding.
        System.Collections.ArrayList customers = new System.Collections.ArrayList();
        customers.Add(new Customer("Harry"));
        customers.Add(new Customer("Sally"));
        customers.Add(new Customer("Roy"));
        customers.Add(new Customer("Pris"));

        // Initialize and bind the DataGridView.
        this.dataGridView1.SelectionMode = 
            DataGridViewSelectionMode.FullRowSelect;
        this.dataGridView1.AutoGenerateColumns = true;
        this.dataGridView1.DataSource = customers;
    }

    // Calls the SendInvoice() method for the Customer 
    // object bound to each selected row.
    void invoiceButton_Click(object sender, EventArgs e)
    {
        foreach (DataGridViewRow row in this.dataGridView1.SelectedRows)
        {
            Customer cust = row.DataBoundItem as Customer;
            if (cust != null)
            {
                cust.SendInvoice();
            }
        }
    }
}

public class Customer
{
    private String nameValue;

    public Customer(String name)
    {
        nameValue = name;
    }

    public String Name
    {
        get
        {
            return nameValue;
        }
        set 
        {
            nameValue = value;
        }
    }

    public void SendInvoice()
    {
        MessageBox.Show(nameValue + " has been billed.");
    }
}

编译代码

此示例需要:

  • 对 System 和 System.Windows.Forms 程序集的引用。

有关从 Visual Basic 或 Visual C# 的命令行生成此示例的信息,请参见从命令行生成 (Visual Basic)在命令行上使用 csc.exe 生成。 也可以通过将代码粘贴到新项目,在 Visual Studio 中生成此示例。 有关更多信息,请参见 如何:使用 Visual Studio 编译和运行完整的 Windows 窗体代码示例如何:使用 Visual Studio 编译和运行完整的 Windows 窗体代码示例如何:使用 Visual Studio 编译和运行完整的 Windows 窗体代码示例如何:使用 Visual Studio 编译和运行完整的 Windows 窗体代码示例如何:使用 Visual Studio 编译和运行完整的 Windows 窗体代码示例.

请参见

任务

如何:将对象绑定到 Windows 窗体 DataGridView 控件

参考

DataGridView

DataGridViewRow

DataGridViewRow.DataBoundItem

其他资源

在 Windows 窗体 DataGridView 控件中显示数据