【EF core】App.config 的配置

1、添加 App.Config 文件，并且配置数据库的相对位置

 

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
    <connectionStrings >
        <!--点号 表示相对目录 -->
        <add name="SqliteConnection"  connectionString="Data Source=.\Resources\Data\text.db;"     providerName="system.Data.SQLite"/>
    </connectionStrings>
</configuration>

当出现这种错误，是路径未生成生成， Debug问价夹 下Resources\Data 下是否存在 这两个文件夹。

 

 

2、EF core 的DbContext中配置如下：

using Microsoft.Data.Sqlite;
using Microsoft.EntityFrameworkCore;
using System;
using System.Collections.Generic;
using System.Configuration;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace IndividualQAlibrary.MVVM.Models
{
    internal class TestDataContext:DbContext
    {
        public DbSet<Programming> Programmings { get; set; }

        string connectionString;
        public TestDataContext()
        {
            connectionString = ConfigurationManager.ConnectionStrings["SqliteConnection"].ConnectionString;
        }
        protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
        {
            base.OnConfiguring(optionsBuilder);


            var builder = new SqliteConnectionStringBuilder(connectionString);
            optionsBuilder.UseSqlite(connectionString);

        }
        protected override void OnModelCreating(ModelBuilder modelBuilder)
        {

         
            base.OnModelCreating(modelBuilder);
           
        }

    }
}

3、实体

using System;
using System.Collections.Generic;

namespace IndividualQAlibrary.MVVM.Models;

public partial class Programming
{
    public int? Id { get; set; }

    public string? Questiontype { get; set; }

    public string? Content { get; set; }

    public int? Numberoferrors { get; set; }

    public string? Answer { get; set; }

    public string? Classify { get; set; }

    public string? Creationtime { get; set; }

    public string? Remark { get; set; }
}

 

4、wpf 窗体代码

using IndividualQAlibrary.MVVM.Models;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Shapes;

namespace IndividualQAlibrary.MVVM.Views
{
    /// <summary>
    /// QAlibraryView.xaml 的交互逻辑
    /// </summary>
    public partial class QAlibraryView : Window
    {
        public QAlibraryView()
        {
            InitializeComponent();
        }

        private void Button_Click(object sender, RoutedEventArgs e)
        {
            TestDataContext test = new TestDataContext();
            test.Database.EnsureCreated();
        }
    }
}

 点击按钮后生成数据库

5、生成 数据库