From bf29b98c1cbf8e1222584587c9ad1ef72de9b9d9 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E9=99=88=E6=A2=A6=E6=B6=B5?= <3234558314@qq.com>
Date: Mon, 23 Dec 2024 08:11:39 +0800
Subject: [PATCH] 1218

---
 ...45\346\225\260\346\215\256\345\272\223.md" | 130 ++++++++++++++++++
 1 file changed, 130 insertions(+)

diff --git "a/\351\231\210\346\242\246\346\266\265/20241218\350\277\236\346\216\245\346\225\260\346\215\256\345\272\223.md" "b/\351\231\210\346\242\246\346\266\265/20241218\350\277\236\346\216\245\346\225\260\346\215\256\345\272\223.md"
index e69de29..d10bc12 100644
--- "a/\351\231\210\346\242\246\346\266\265/20241218\350\277\236\346\216\245\346\225\260\346\215\256\345\272\223.md"
+++ "b/\351\231\210\346\242\246\346\266\265/20241218\350\277\236\346\216\245\346\225\260\346\215\256\345\272\223.md"
@@ -0,0 +1,130 @@
+## 连接实际数据库
+1. 一个构造函数
+```js
+ privite readonly 模型连接名 变量名;
+    public 控制器名(){
+        _db = new 模型连接名();
+    }
+```
+
+### 必要条件(一些安装命令)
+1. 下载安装包：dotnet add package Microsoft.EntityFrameworkCore.SqlServer
+2. 下载安装包：dotnet add package Microsoft.EntityFrameworkCore.Design
+3. 下载ef工具：dotnet tool install --global dotnet-ef
+4. 生成迁移文件：dotnet ef migrations add Info
+5. 将迁移文件更新到数据库:dotnet ef database update
+
+### 代码练习
+2. 在控制器中的代码(返回的是最简单的视图)
+
+```cs
+using Microsoft.AspNetCore.Mvc;
+using StuInfo.Models;
+
+namespace StuInfo.Controllers;
+
+public class StudentsController:Controller
+{
+    private readonly StuContext _db;
+    public  StudentsController(){
+        _db=new StuContext();
+    }
+    // 查询
+    public IActionResult Index(int id)
+    {
+       var res=_db.Students.FirstOrDefault(x=>x.Id ==id);
+        return View(res);
+    }
+    public IActionResult Create(int id)
+    {
+        var res=_db.Students.FirstOrDefault(x=>x.Id ==id);
+        return View(res);
+    }
+    public IActionResult Edit(int id)
+    {
+        var res=_db.Students.FirstOrDefault(x=>x.Id ==id);
+        return View(res);
+    }
+    public IActionResult Delete(int id)
+    {
+        var res=_db.Students.FirstOrDefault(x=>x.Id == id);
+        return View(res);
+    }
+}
+```
+3. 数据表中的数据
+```js
+namespace StuInfo.Models;
+
+// 学生信息表
+public class Student
+{
+    // 主键id
+    public int Id{get;set;}
+    // 学号
+    public string StuCore{get;set;}=null!;
+    // 学生姓名
+    public string StuName{get;set;}=null!;
+}
+```
+4. 连接、创建数据库代码
+```cs
+namespace StuInfo.Models;
+
+using Microsoft.EntityFrameworkCore;
+
+public class StuContext : DbContext
+{
+    public DbSet<Student> Students {get;set;}=null!;
+    public DbSet<Teacher> Teachers{get;set;}=null!;
+
+    // 调用OnConfiguring方法
+    protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
+    {
+        base.OnConfiguring(optionsBuilder);
+
+        var connectionString=$"server=.\\SQLEXPRESS;database=MyStuDb;uid=sa;pwd=123456;TrustServerCertificate=true;";
+
+        optionsBuilder.UseSqlServer(connectionString);
+    }
+}
+```
+5. 视图内的代码
+```html
+<!-- Index内代码 -->
+@model List<Student>;
+
+@* 查询 *@
+<div>
+    <form asp-action="Index" method="get">
+        <label for=""><input placeholder="请输入关键字" name="keyword"></label>
+        <button type="submit">查找</button>
+    </form>
+</div>
+<div>
+    <a asp-action="Create">新增</a>
+</div>
+<table>
+    <thead>
+        <th>ID</th>
+        <th>学生学号</th>
+        <th>学生姓名</th>
+        <th>操作</th>
+    </thead>
+    <tbody>
+        @foreach (var item in Model)
+        {
+        <tr>
+            <td>@item.Id</td>
+            <td>@item.StuCore</td>
+            <td>@item.StuName</td>
+            <td>
+                <a asp-action="Edit" asp-route-id="@item.Id">修改</a>
+                <a asp-action="Delete" asp-route-id="@item.Id">删除</a>
+            </td>
+           </tr>
+        }
+            
+    </tbody>
+</table>
+```
\ No newline at end of file
-- 
Gitee