下面的代码示例演示如何验证由用户输入到 DataGridView 控件中的数据。 在此示例中，使用 Northwind 示例数据的 Customers 表中的行填充 DataGridView 。 用户编辑 CompanyName 列中的单元格时，通过检查单元格不为空而测试其值的有效性。 如果 CellValidating 事件的事件处理程序发现该值为空字符串， DataGridView 会阻止用户退出单元格，直到输入了一个非空字符串。

有关此代码示例的完整说明，请参阅 演练：验证 Windows 窗体 DataGridView 控件中的数据 。

using System;
using System.Data;
using System.Data.SqlClient;
using System.Windows.Forms;
public class Form1 : System.Windows.Forms.Form
    private DataGridView dataGridView1 = new DataGridView();
    private BindingSource bindingSource1 = new BindingSource();
    public Form1()
        // Initialize the form.
        this.dataGridView1.Dock = DockStyle.Fill;
        this.Controls.Add(dataGridView1);
        this.Load += new EventHandler(Form1_Load);
        this.Text = "DataGridView validation demo (disallows empty CompanyName)";
    private void Form1_Load(System.Object sender, System.EventArgs e)
        // Attach DataGridView events to the corresponding event handlers.
        this.dataGridView1.CellValidating += new
            DataGridViewCellValidatingEventHandler(dataGridView1_CellValidating);
        this.dataGridView1.CellEndEdit += new
            DataGridViewCellEventHandler(dataGridView1_CellEndEdit);
        // Initialize the BindingSource and bind the DataGridView to it.
        bindingSource1.DataSource = GetData("select * from Customers");
        this.dataGridView1.DataSource = bindingSource1;
        this.dataGridView1.AutoResizeColumns(
            DataGridViewAutoSizeColumnsMode.AllCellsExceptHeader);
    private void dataGridView1_CellValidating(object sender,
        DataGridViewCellValidatingEventArgs e)
        string headerText =
            dataGridView1.Columns[e.ColumnIndex].HeaderText;
        // Abort validation if cell is not in the CompanyName column.
        if (!headerText.Equals("CompanyName")) return;
        // Confirm that the cell is not empty.
        if (string.IsNullOrEmpty(e.FormattedValue.ToString()))
            dataGridView1.Rows[e.RowIndex].ErrorText =
                "Company Name must not be empty";
            e.Cancel = true;
    void dataGridView1_CellEndEdit(object sender, DataGridViewCellEventArgs e)
        // Clear the row error in case the user presses ESC.
        dataGridView1.Rows[e.RowIndex].ErrorText = String.Empty;
    private static DataTable GetData(string selectCommand)
        string connectionString =
            "Integrated Security=SSPI;Persist Security Info=False;" +
            "Initial Catalog=Northwind;Data Source=localhost;Packet Size=4096";
        // Connect to the database and fill a data table.
        SqlDataAdapter adapter =
            new SqlDataAdapter(selectCommand, connectionString);
        DataTable data = new DataTable();
        data.Locale = System.Globalization.CultureInfo.InvariantCulture;
        adapter.Fill(data);
        return data;
    [STAThread]
    static void Main()
        Application.EnableVisualStyles();
        Application.Run(new Form1());

Imports System.Data
Imports System.Data.SqlClient
Imports System.Windows.Forms
Public Class Form1
    Inherits System.Windows.Forms.Form
    Private WithEvents dataGridView1 As New DataGridView()
    Private bindingSource1 As New BindingSource()
    Public Sub New()
        ' Initialize the form.
        Me.dataGridView1.Dock = DockStyle.Fill
        Me.Controls.Add(dataGridView1)
        Me.Text = "DataGridView validation demo (disallows empty CompanyName)"
    End Sub
    Private Sub Form1_Load(ByVal sender As System.Object, _
        ByVal e As System.EventArgs) Handles Me.Load
        ' Initialize the BindingSource and bind the DataGridView to it.
        bindingSource1.DataSource = GetData("select * from Customers")
        Me.dataGridView1.DataSource = bindingSource1
        Me.dataGridView1.AutoResizeColumns( _
            DataGridViewAutoSizeColumnsMode.AllCellsExceptHeader)
    End Sub
    Private Sub dataGridView1_CellValidating(ByVal sender As Object, _
        ByVal e As DataGridViewCellValidatingEventArgs) _
        Handles dataGridView1.CellValidating
        Dim headerText As String = _
            dataGridView1.Columns(e.ColumnIndex).HeaderText
        ' Abort validation if cell is not in the CompanyName column.
        If Not headerText.Equals("CompanyName") Then Return
        ' Confirm that the cell is not empty.
        If (String.IsNullOrEmpty(e.FormattedValue.ToString())) Then
            dataGridView1.Rows(e.RowIndex).ErrorText = _
                "Company Name must not be empty"
            e.Cancel = True
        End If
    End Sub
    Private Sub dataGridView1_CellEndEdit(ByVal sender As Object, _
        ByVal e As System.Windows.Forms.DataGridViewCellEventArgs) _
        Handles dataGridView1.CellEndEdit
        ' Clear the row error in case the user presses ESC.   
        dataGridView1.Rows(e.RowIndex).ErrorText = String.Empty
    End Sub
    Private Shared Function GetData(ByVal selectCommand As String) As DataTable
        Dim connectionString As String = _
            "Integrated Security=SSPI;Persist Security Info=False;" + _
            "Initial Catalog=Northwind;Data Source=localhost;Packet Size=4096"
        ' Connect to the database and fill a data table.
        Dim adapter As New SqlDataAdapter(selectCommand, connectionString)
        Dim data As New DataTable()
        data.Locale = System.Globalization.CultureInfo.InvariantCulture
        adapter.Fill(data)
        Return data
    End Function
    <STAThread()> _
    Shared Sub Main()
        Application.EnableVisualStyles()
        Application.Run(New Form1())
    End Sub
End Class
此示例需要：
引用 System、System.Data、System.Windows.Forms 和 System.XML 程序集。
.NET Framework 安全性
将敏感信息（如密码）存储在连接字符串中可能会影响应用程序的安全性。 若要控制对数据库的访问，一种较为安全的方法是使用 Windows 身份验证（也称为集成安全性）。 有关详细信息，请参阅保护连接信息。
DataGridView
BindingSource
演练：在 Windows 窗体 DataGridView 控件中验证数据
Windows 窗体 DataGridView 控件中的数据输入
演练：处理在 Windows 窗体 DataGridView 控件中输入数据时发生的错误
保护连接信息