一、SQLite数据库介绍
SQLite是一款轻量级的关系型数据库，它小巧高效，无需服务器配置，仅需单一文件即可存储数据。SQLite跨平台支持，易于集成到各种应用程序中，并支持SQL语言进行数据操作。它保证了数据的完整性、一致性和持久性，通过文件级锁定实现并发访问的安全。SQLite广泛应用于移动、桌面和嵌入式系统，是管理本地数据的理想选择。其长期稳定性和开发团队的支持承诺，使其成为数字内容存储的可靠选择。
二、效果演示：
三、项目结构：
1.项目结构
2.数据库内容
四、例子代码
C#项目中安装System.Data.SQLite。这可以通过NuGet包管理器来完成。在Visual Studio中，你可以通过“管理NuGet包”来搜索并安装System.Data.SQLite。
1.前端Xaml文件
<Grid ><Grid.RowDefinitions><RowDefinition Height="120"/><RowDefinition Height="50"/><RowDefinition Height="50"/><RowDefinition Height="50"/><RowDefinition Height="auto"/></Grid.RowDefinitions><Button Content="数据创建" HorizontalAlignment="Left" Click="DataAddition" Height="30" Margin="30,0,0,0"/><StackPanel Grid.Row="1" Orientation="Horizontal" HorizontalAlignment="Center" VerticalAlignment="Center"><TextBlock Text="用户名：" Margin="0,5,0,0"/><TextBox x:Name="txtUsername" Width="200" Height="30" Margin="0,0,15,0"/></StackPanel><StackPanel Grid.Row="2" Orientation="Horizontal" HorizontalAlignment="Center" VerticalAlignment="Center"><TextBlock Text="密 码：" Margin="0,5,0,0"/><PasswordBox x:Name="txtPassword" Width="200" Height="30" Margin="0,0,15,0"/></StackPanel><StackPanel Grid.Row="3" HorizontalAlignment="Center" VerticalAlignment="Center"><Button Content="登录" Background="#0047AB" Foreground="White" HorizontalAlignment="Right" Click="LoginButton_Click" Width="200" Height="30" Margin="30,0,0,0"/></StackPanel><TextBlock Grid.Row="4" x:Name="myTextBlock" HorizontalAlignment="Center" VerticalAlignment="Center" FontSize="14"/></Grid>2.后端Cs文件
public partial class MainWindow : Window{string dbConnectionString = "Data Source=D:\\Quality managemen program\\UpperComputer\\列子程序\\tryWpfApp3-sq用户登录\\WpfApp1\\date\\mydatabase.db; Version=3;";public MainWindow(){InitializeComponent();using (var connection = new SQLiteConnection(dbConnectionString)){connection.Open();// 创建表（如果尚不存在） CreateTable(connection);}}private void DataAddition(object sender, RoutedEventArgs e){using (var connection = new SQLiteConnection(dbConnectionString)){connection.Open();for (int i = 0; i < 10; i++){// 插入数据 InsertData(connection);} }}private void LoginButton_Click(object sender, RoutedEventArgs e){string input_name = txtUsername.Text;string input_password = txtPassword.Password;using (var connection = new SQLiteConnection(dbConnectionString)){connection.Open();string querySql = "SELECT * FROM Users";using (var command = new SQLiteCommand(querySql, connection))using (var reader = command.ExecuteReader()){int UserPermissions = 0;while (reader.Read()){int id = reader.GetInt32(0);string name = reader.GetString(1);string password = reader.GetString(2);int permissions = reader.GetInt32(3);Debug.WriteLine($"ID: {id}, Name: {name}, PassWord: {password}, Permissions: {permissions}");if (name == input_name && password == input_password){UserPermissions = permissions;}}Debug.WriteLine($"当前权限为{UserPermissions}");myTextBlock.Text = $"当前权限为{UserPermissions}";}}}/*//*/// 创建表static void CreateTable(SQLiteConnection connection){string createTableSql = "CREATE TABLE IF NOT EXISTS Users (" +"Id INTEGER PRIMARY KEY AUTOINCREMENT, " +"Name TEXT NOT NULL, " +"PassWord TEXT, " +"Permissions INT)";using (var command = new SQLiteCommand(createTableSql, connection)){command.ExecuteNonQuery();}}// 插入数据 static void InsertData(SQLiteConnection connection){string insertSql = "INSERT INTO Users (Name, PassWord, Permissions) VALUES (@name, @password, @permissions)";using (var command = new SQLiteCommand(insertSql, connection)){command.Parameters.AddWithValue("@name", "John Doe");command.Parameters.AddWithValue("@password", "123456");command.Parameters.AddWithValue("@permissions", 1);command.ExecuteNonQuery();// 可以插入多条数据，只需重复上述过程即可 }}// 查询数据 static void ReadData(SQLiteConnection connection){string querySql = "SELECT * FROM Users";using (var command = new SQLiteCommand(querySql, connection))using (var reader = command.ExecuteReader()){int UserPermissions = 0;while (reader.Read()){int id = reader.GetInt32(0);string name = reader.GetString(1);string password = reader.GetString(2);int permissions = reader.GetInt32(3);Debug.WriteLine($"ID: {id}, Name: {name}, PassWord: {password}, Permissions: {permissions}");if (name == "AA" && password == "999999"){UserPermissions = permissions;}}Debug.WriteLine($"当前权限为{UserPermissions}");}}// 更新数据 static void UpdateData(SQLiteConnection connection){string updateSql = "UPDATE Users SET PassWord = @newPassWord WHERE Id = @id";using (var command = new SQLiteCommand(updateSql, connection)){command.Parameters.AddWithValue("@newPassWord", "8888");command.Parameters.AddWithValue("@id", 3);command.ExecuteNonQuery();}}}五、C#控制台数据库读写方法例子
using System;
using System.Data.SQLite; // 引入SQLite命名空间 class Program
{static void Main(string[] args){// 数据库连接字符串 string dbConnectionString = "Data Source=D:\\Quality managemen program\\UpperComputer\\C#K\\读写SQlite数据库\\ConsoleApp1\\data\\mydatabase.db; Version=3;";// 创建并连接到SQLite数据库 using (var connection = new SQLiteConnection(dbConnectionString)){connection.Open();// 创建表（如果尚不存在） CreateTable(connection);for (int i = 0; i < 10; i++){// 插入数据 InsertData(connection);}// 查询数据 ReadData(connection);更新数据 //UpdateData(connection);再次查询数据以查看更新 //ReadData(connection);}Console.WriteLine("Press any key to exit...");Console.ReadKey();}// 创建表static void CreateTable(SQLiteConnection connection){string createTableSql = "CREATE TABLE IF NOT EXISTS Users (" +"Id INTEGER PRIMARY KEY AUTOINCREMENT, " +"Name TEXT NOT NULL, " +"PassWord TEXT, " +"Permissions INT)";using (var command = new SQLiteCommand(createTableSql, connection)){command.ExecuteNonQuery();}}// 插入数据 static void InsertData(SQLiteConnection connection){string insertSql = "INSERT INTO Users (Name, PassWord, Permissions) VALUES (@name, @password, @permissions)";using (var command = new SQLiteCommand(insertSql, connection)){command.Parameters.AddWithValue("@name", "John Doe");command.Parameters.AddWithValue("@password", "123456");command.Parameters.AddWithValue("@permissions", 1);command.ExecuteNonQuery();// 可以插入多条数据，只需重复上述过程即可 }}// 查询数据 static void ReadData(SQLiteConnection connection){string querySql = "SELECT * FROM Users";using (var command = new SQLiteCommand(querySql, connection))using (var reader = command.ExecuteReader()){int UserPermissions = 0;while (reader.Read()){int id = reader.GetInt32(0);string name = reader.GetString(1);string password = reader.GetString(2);int permissions = reader.GetInt32(3);Console.WriteLine($"ID: {id}, Name: {name}, PassWord: {password}, Permissions: {permissions}");if (name =="AA" && password=="999999"){UserPermissions = permissions;}}Console.WriteLine($"当前权限为{UserPermissions}");}}// 更新数据 static void UpdateData(SQLiteConnection connection){string updateSql = "UPDATE Users SET PassWord = @newPassWord WHERE Id = @id";using (var command = new SQLiteCommand(updateSql, connection)){command.Parameters.AddWithValue("@newPassWord", "8888");command.Parameters.AddWithValue("@id", 3); command.ExecuteNonQuery();}}
}
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