无法使用C#、WPF将数据保存到SQLite数据库

Question

我正在使用 Visual Studio 2022 以及 C# 和 WPF 应用程序来创建桌面应用程序。 SQLite 是数据库。下面是代码。

数据库表代码

CREATE TABLE "Disclaimer" (
    "ID"    INTEGER,
    "DisName"   TEXT,
    "DisDateTime"   TEXT,
    PRIMARY KEY("ID" AUTOINCREMENT)
);

应用程序.xaml

<Application x:Class="Sanganak.App"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:system="clr-namespace:System;assembly=mscorlib"
             StartupUri="Splash.xaml">
    <Application.Resources>
        <ResourceDictionary>
            <system:String x:Key="SQLiteConnection">Data Source=|DataDirectory|\Sanganak.db;Version=3;</system:String>
        </ResourceDictionary>
    </Application.Resources>
</Application>

背后的C#代码

 private void Button1_Click(object sender, RoutedEventArgs e)
 {
     try
     {
         // Get the system name
         string systemName = Environment.MachineName;
         // Get the current date and time
         DateTime currentDateAndTime = DateTime.Now;

         // Save data to Sanganak database
         string connectionString = (string)Application.Current.Resources["SQLiteConnection"];
         using (SQLiteConnection connection = new SQLiteConnection(connectionString))
         {
             connection.Open();
             string sql = "INSERT INTO Disclaimer (DisName, DisDateTime) VALUES (@DisName, @DisDateTime)";
             using (SQLiteCommand command = new SQLiteCommand(sql, connection))
             {
                 command.Parameters.AddWithValue("@DisName", systemName);
                 command.Parameters.AddWithValue("@DisDateTime", currentDateAndTime.ToString("yyyy-MM-dd HH:mm:ss"));
                 command.ExecuteNonQuery();
             }
             connection.Close();
         }
         Hide();
         var setupWindow = new SetUp();
         setupWindow.Show();
     }
     catch (Exception ex)
     {
         // Log the exception (replace with your actual logging mechanism)
         Console.WriteLine("Exception: " + ex.Message);
     }
 }

如果我在后面的 C# 代码中更改表的名称，则会出现“找不到表”错误。这意味着路径和连接是正确的。但是运行代码后，如果我使用数据库浏览器检查表，它仍然是空的。

hide()

和显示窗口工作正常。该代码要么跳过数据库部分，要么更新表但不保存它。我尝试为

connection.open()

和

command.ExecuteNonQuery()

添加错误处理程序，但它没有捕获错误。程序运行顺利，只是数据库表中没有数据。

Answer 1

代码好像有问题。这是实际有效的代码。

private void Button1_Click(object sender, RoutedEventArgs e)

{ 尝试 { // 获取系统名称 字符串系统名称=环境.机器名称; // 获取当前日期和时间 日期时间 currentDateAndTime = DateTime.Now;

    // Save data to Sanganak database
    string connectionString = (string)Application.Current.Resources["SQLiteConnection"];
    using (SQLiteConnection connection = new SQLiteConnection(connectionString))
    {
        connection.Open();

        if (connection.State != ConnectionState.Open)
        {
            throw new InvalidOperationException("Failed to open the SQLite connection.");
        }

        // Now that the connection is open, proceed with the database operation
        string sql = "INSERT INTO Disclaimer (DisName, DisDateTime) VALUES (@DisName, @DisDateTime)";
        using (SQLiteCommand command = new SQLiteCommand(sql, connection))
        {
            command.Parameters.AddWithValue("@DisName", systemName);
            command.Parameters.AddWithValue("@DisDateTime", currentDateAndTime.ToString("yyyy-MM-dd HH:mm:ss"));
            command.ExecuteNonQuery();
        }

        // No need to close the connection explicitly, as 'using' block takes care of it
    }

    Hide();
    var setupWindow = new SetUp();
    setupWindow.Show();
}
catch (Exception ex)
{
    // Log the exception (replace with your actual logging mechanism)
    Console.WriteLine("Exception: " + ex.Message);
}

}