如何在C# Windows Forms应用中点击按钮打开文件浏览器选择Access文件

我正在用Windows Forms开发待办事项清单应用，对接MS Access数据库。需要实现点击loadButton时弹出文件浏览器选择Access文件，并将DataGrid中的待办事项导出到该文件中。现有代码如下：

using System.Data;
using System.Windows.Forms;
using System.Data.OleDb;
using System.Diagnostics;

namespace todolistApp
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        DataTable todoList = new DataTable();
        bool isEditing = false;
        private void Form1_Load(object sender, EventArgs e)
        {
            todoList.Columns.Add("Title");
            todoList.Columns.Add("Description");

            todolistView.DataSource = todoList;
        }

        private void newButton_Click(object sender, EventArgs e)
        {
            titletextBox.Text = "";
            descriptiontextBox.Text = "";
        }

        private void editButton_Click(object sender, EventArgs e)
        {
            isEditing = true;

            titletextBox.Text = todoList.Rows[todolistView.CurrentCell.RowIndex].ItemArray[0].ToString();
            descriptiontextBox.Text = todoList.Rows[todolistView.CurrentCell.RowIndex].ItemArray[1].ToString();
        }

        private void deleteButton_Click(object sender, EventArgs e)
        {
            try
            {
                todoList.Rows[todolistView.CurrentCell.RowIndex].Delete();
            }
            catch (Exception ex)
            {
                Console.WriteLine("Error: " + ex);
            }
        }

        private void button3_Click(object sender, EventArgs e)
        {
            if (isEditing)
            {
                todoList.Rows[todolistView.CurrentCell.RowIndex]["Title"] = titletextBox.Text;
                todoList.Rows[todolistView.CurrentCell.RowIndex]["Description"] = titletextBox.Text;
            }
            else
            {
                todoList.Rows.Add(titletextBox.Text, descriptiontextBox.Text);
            }
            titletextBox.Text = "";
            descriptiontextBox.Text = "";
            isEditing = false;

        }

        private void insertButton_Click(object sender, EventArgs e)
        {
            foreach (DataRow row in todoList.Rows)
            {
                string constring = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=\"E:\Downloads\coding stuf\todolistApp\todolistApp\todolistDB.accdb\"";
                using (OleDbConnection con = new OleDbConnection(constring))
                {
                    using (OleDbCommand cmd = new OleDbCommand("INSERT INTO Table1 ([Title], [Description]) VALUES (@title,@description)", con))
                    {
                        cmd.Parameters.AddWithValue("@title", row["Title"].ToString());
                        cmd.Parameters.AddWithValue("@description", row["Description"].ToString());

                        con.Open();
                        cmd.ExecuteNonQuery();
                        con.Close();
                    }
                }
            }

            MessageBox.Show("All rows inserted.");
        }

        private void loadButton_Click(object sender, EventArgs e)
        {

        }
    }
}

解决方案 #

1. 核心实现逻辑

使用Windows Forms内置的OpenFileDialog控件弹出文件选择窗口，筛选Access格式文件；再封装数据导出方法，将DataTable中的待办事项写入选中的Access文件。同时修复原代码中的小问题，提升程序稳定性。

2. 修改后的完整代码

using System.Data;
using System.Windows.Forms;
using System.Data.OleDb;

namespace todolistApp
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        DataTable todoList = new DataTable();
        bool isEditing = false;

        private void Form1_Load(object sender, EventArgs e)
        {
            todoList.Columns.Add("Title");
            todoList.Columns.Add("Description");
            todolistView.DataSource = todoList;
        }

        private void newButton_Click(object sender, EventArgs e)
        {
            titletextBox.Text = "";
            descriptiontextBox.Text = "";
        }

        private void editButton_Click(object sender, EventArgs e)
        {
            if (todolistView.CurrentCell == null) return;
            
            isEditing = true;
            var currentRow = todoList.Rows[todolistView.CurrentCell.RowIndex];
            titletextBox.Text = currentRow["Title"].ToString();
            descriptiontextBox.Text = currentRow["Description"].ToString();
        }

        private void deleteButton_Click(object sender, EventArgs e)
        {
            try
            {
                if (todolistView.CurrentCell != null)
                {
                    todoList.Rows[todolistView.CurrentCell.RowIndex].Delete();
                }
            }
            catch (Exception ex)
            {
                MessageBox.Show($"删除错误: {ex.Message}");
            }
        }

        private void button3_Click(object sender, EventArgs e)
        {
            if (string.IsNullOrWhiteSpace(titletextBox.Text))
            {
                MessageBox.Show("请输入标题");
                return;
            }

            if (isEditing && todolistView.CurrentCell != null)
            {
                var currentRow = todoList.Rows[todolistView.CurrentCell.RowIndex];
                currentRow["Title"] = titletextBox.Text;
                currentRow["Description"] = descriptiontextBox.Text; // 修复原赋值错误
            }
            else
            {
                todoList.Rows.Add(titletextBox.Text, descriptiontextBox.Text);
            }

            titletextBox.Text = "";
            descriptiontextBox.Text = "";
            isEditing = false;
        }

        private void insertButton_Click(object sender, EventArgs e)
        {
            if (todoList.Rows.Count == 0)
            {
                MessageBox.Show("没有数据可插入");
                return;
            }

            string constring = @"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=""E:\Downloads\coding stuf\todolistApp\todolistApp\todolistDB.accdb""";
            using (OleDbConnection con = new OleDbConnection(constring))
            {
                con.Open();
                using (OleDbCommand cmd = new OleDbCommand("INSERT INTO Table1 ([Title], [Description]) VALUES (@title,@description)", con))
                {
                    cmd.Parameters.Add("@title", OleDbType.VarChar);
                    cmd.Parameters.Add("@description", OleDbType.VarChar);

                    foreach (DataRow row in todoList.Rows)
                    {
                        cmd.Parameters["@title"].Value = row["Title"].ToString();
                        cmd.Parameters["@description"].Value = row["Description"].ToString();
                        cmd.ExecuteNonQuery();
                    }
                }
                con.Close();
            }

            MessageBox.Show("All rows inserted.");
        }

        private void loadButton_Click(object sender, EventArgs e)
        {
            // 创建文件选择对话框
            using (OpenFileDialog openFileDialog = new OpenFileDialog())
            {
                // 设置筛选器，仅显示Access文件
                openFileDialog.Filter = "Access数据库文件 (*.accdb)|*.accdb|旧版Access文件 (*.mdb)|*.mdb";
                openFileDialog.Title = "选择Access数据库文件";

                // 用户选择文件并确认后执行导出
                if (openFileDialog.ShowDialog() == DialogResult.OK)
                {
                    string selectedFilePath = openFileDialog.FileName;
                    ExportDataToAccess(selectedFilePath);
                }
            }
        }

        // 封装数据导出逻辑
        private void ExportDataToAccess(string filePath)
        {
            if (todoList.Rows.Count == 0)
            {
                MessageBox.Show("没有数据可导出");
                return;
            }

            // 构建目标文件连接字符串
            string constring = $"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=\"{filePath}\"";
            
            try
            {
                using (OleDbConnection con = new OleDbConnection(constring))
                {
                    con.Open();
                    // 假设目标文件已存在Table1表，结构为Title(文本)、Description(文本)
                    using (OleDbCommand cmd = new OleDbCommand("INSERT INTO Table1 ([Title], [Description]) VALUES (@title,@description)", con))
                    {
                        cmd.Parameters.Add("@title", OleDbType.VarChar);
                        cmd.Parameters.Add("@description", OleDbType.VarChar);

                        foreach (DataRow row in todoList.Rows)
                        {
                            cmd.Parameters["@title"].Value = row["Title"].ToString();
                            cmd.Parameters["@description"].Value = row["Description"].ToString();
                            cmd.ExecuteNonQuery();
                        }
                    }
                    con.Close();
                    MessageBox.Show("数据导出成功");
                }
            }
            catch (Exception ex)
            {
                MessageBox.Show($"导出错误: {ex.Message}");
            }
        }
    }
}

3. 关键说明

• OpenFileDialog的Filter属性限制可选文件类型，避免用户选择非Access文件
• 新增ExportDataToAccess方法封装导出逻辑，提升代码复用性
• 补充空数据判断、异常捕获，避免程序崩溃
• 修复原代码中button3_Click里描述字段的赋值错误
• 优化insertButton_Click中的数据库连接使用，避免循环内重复创建连接

内容的提问来源于stack exchange，提问作者welive.welove.welie