ASP.NET CORE 入门教程(附源码)

时间:2024-08-20 16:08:08

ASP.NET CORE 入门教程

第一课 基本概念

  • 基本概念
    • Asp.Net Core Mvc是.NET Core平台下的一种Web应用开发框架
      • 符合Web应用特点
      • .NET Core跨平台解决方案
      • MVC设计模式的一种实现
  • 环境准备

第二课 控制器的介绍

  • 控制器定义方式:
    • 命名以Controller结尾
    • 使用ControllerAttribute标注
    public class TestController : Controller
{ } [Controller]
public class Test : Controller
{ }
  • 默认路由规则

    • 域名/控制器类/方法
    • {Domain}/{Controller}/{Action}
  • 数据形式

    • QueryString: ?name=zhangsan&age=22
    • Form
    • Cookie
    • Session
    • Header
  • HttpRequest

    • HttpRequest 是用户请求对象
    • 提供获取请求数据的属性
      • Cookies,Headers,Query,QueryString,Form
        public IActionResult Hello()
{
// Query
var name = Request.Query["name"];
// QueryString
var query = Request.QueryString.Value;
// Form
var username = Request.Form["username"];
// Cookies
var cookie = Request.Cookies["item"];
// Headers
var headers = Request.Headers["salt"]; return Content("Hello");
}
  • HttpContext
    • HttpContext是用户请求上下文
    • 提供Session属性获取Session对象
      • Session.Set 设置
      • Session.Remove 移除
      • Session.TryGetValue 获取数据
        public IActionResult Hello()
{
// byte[]
HttpContext.Session.Set("byte", new byte[] { 1, 2, 3, 4, 5 });
var bytes = HttpContext.Session.Get("byte");
// string
HttpContext.Session.SetString("name", "tom");
var name = HttpContext.Session.GetString("name");
// int
HttpContext.Session.SetInt32("id", 20);
var id = HttpContext.Session.GetInt32("id");
HttpContext.Session.Remove("name");
HttpContext.Session.Clear(); return Content("Hello");
}
  • 数据绑定
    • 把用户请求的数据绑定到控制器方法的参数上
    • 支持简单类型与自定义类型
    • 绑定规则是请求数据名称与参数名称一致
      • 如查询字符串key名称跟参数一致
      • Form表单名称跟参数一致
        public IActionResult Hello(RequestModel request,int? age)
{
// 查询字符串
var test = Request.Query["test"];
// 简单类型
var userAge = age;
// 自定义类型
var name = request.Name; return Content("Hello");
} public class RequestModel
{
public string Name { get; set; }
}
  • 内容补充
    • 如果以Controller结尾的都是控制器,那如果程序里面由一些业务命名的时候也是以Controller结尾,怎么办?
    • NonControllerAttribute
    /// <summary>
/// 拍卖师控制类
/// </summary>
[NonController]
public class AuctionController
{ }
  • 常用特性
特性 数据源
FromHeaderAttribute 请求头数据
FromRouteAttribute 路由数据
FromBodyAttribute 请求体
FromFormAttribute 表单数据
FromQueryAttribute 查询字符串
FromServicesAttribute 服务注册
        public IActionResult Say(
[FromForm]string name,
[FromQuery]int age,
[FromHeader] string salt,
[FromBody] string content
)
{
return View();
}
  • 特性参数

    • 通过特性修饰参数来影响绑定逻辑
    • 灵活扩展
  • IActionResult

    • 动作结果接口
    • 具体实现
      • JsonResult:返回JSON结构数据
      • RedirectResult:跳转到新地址
      • FileResult:返回文件
      • ViewResult:返回视图内容
      • ContentResult:文本内容

第三课 视图与表单

  • 数据传递
    • ViewData
    • ViewBag
    • tempData
    • Model
    • Session
    • Cache
ViewData ViewBag
键值对 动态类型
索引器 ViewData的封装
支持任意类型 动态属性
TempData Cache Session
视图级别 应用程序级别 会话级别
只允许消费一次 服务器端保存 服务器端保存
可多次赋值 可设置有效期 键值对形式
键值对形式 键值对形式
  • Cache
    • 与.NET Framework时代不同,一种全新实现
    • IMemoryCache接口
    • 依赖注入方式获取
    • IMemoryCache.Get/Set操作数据
    [Controller]
public class Test : Controller
{
private readonly IMemoryCache _cache; public Test(IMemoryCache memoryCache)
{
this._cache = memoryCache;
} public IActionResult ReadCache()
{
_cache.Set("name","tom");
_cache.Get("name"); _cache.Set("age",30);
_cache.Get("age"); User tom = new User(){ Name = "admin",Pwd = "123456"};
_cache.Set<User>("user",tom);
_cache.Get<User>("user");
return Content("ok");
}
} public class User
{
public string Name { get; set; }
public string Pwd { get; set; }
}
  • ViewStart
    • 以_ViewStart.cshtml命名,固定名称,不能更换
    • 一般放在视图所在目录的根目录下
    • 自动执行,无需手工调用
    • 不要再ViewStart中做大量的业务操作
  • ViewImport
    • 以_ViewImport.cshtml命名,固定名称,不能更换
    • 只作引入操作
    • 一般放在视图所在目录的根目录下
    • 自动执行,无需手工调用
    • 视图中可以使用@using关键字引入所需命名空间
    • 通过ViewImport做全局性的命名空间引入,减少在每个页面中引入的工作量

第四课 数据验证

  • 数据验证特性ValidationAttribute
  public abstract class ValidationAttribute : Attribute
{
/// <summary>Initializes a new instance of the <see cref="T:System.ComponentModel.DataAnnotations.ValidationAttribute"></see> class.</summary>
protected ValidationAttribute(); /// <summary>Initializes a new instance of the <see cref="T:System.ComponentModel.DataAnnotations.ValidationAttribute"></see> class by using the function that enables access to validation resources.</summary>
/// <param name="errorMessageAccessor">The function that enables access to validation resources.</param>
/// <exception cref="T:System.ArgumentNullException"><paramref name="errorMessageAccessor">errorMessageAccessor</paramref> is null.</exception>
protected ValidationAttribute(Func<string> errorMessageAccessor); /// <summary>Initializes a new instance of the <see cref="T:System.ComponentModel.DataAnnotations.ValidationAttribute"></see> class by using the error message to associate with a validation control.</summary>
/// <param name="errorMessage">The error message to associate with a validation control.</param>
protected ValidationAttribute(string errorMessage); /// <summary>Gets or sets an error message to associate with a validation control if validation fails.</summary>
/// <returns>The error message that is associated with the validation control.</returns>
public string ErrorMessage { get; set; } /// <summary>Gets or sets the error message resource name to use in order to look up the <see cref="P:System.ComponentModel.DataAnnotations.ValidationAttribute.ErrorMessageResourceType"></see> property value if validation fails.</summary>
/// <returns>The error message resource that is associated with a validation control.</returns>
public string ErrorMessageResourceName { get; set; } /// <summary>Gets or sets the resource type to use for error-message lookup if validation fails.</summary>
/// <returns>The type of error message that is associated with a validation control.</returns>
public Type ErrorMessageResourceType { get; set; } /// <summary>Gets the localized validation error message.</summary>
/// <returns>The localized validation error message.</returns>
protected string ErrorMessageString { get; } /// <summary>Gets a value that indicates whether the attribute requires validation context.</summary>
/// <returns>true if the attribute requires validation context; otherwise, false.</returns>
public virtual bool RequiresValidationContext { get; } /// <summary>Applies formatting to an error message, based on the data field where the error occurred.</summary>
/// <param name="name">The name to include in the formatted message.</param>
/// <returns>An instance of the formatted error message.</returns>
public virtual string FormatErrorMessage(string name); /// <summary>Checks whether the specified value is valid with respect to the current validation attribute.</summary>
/// <param name="value">The value to validate.</param>
/// <param name="validationContext">The context information about the validation operation.</param>
/// <returns>An instance of the <see cref="System.ComponentModel.DataAnnotations.ValidationResult"></see> class.</returns>
public ValidationResult GetValidationResult(
object value,
ValidationContext validationContext); /// <summary>Determines whether the specified value of the object is valid.</summary>
/// <param name="value">The value of the object to validate.</param>
/// <returns>true if the specified value is valid; otherwise, false.</returns>
public virtual bool IsValid(object value); /// <summary>Validates the specified value with respect to the current validation attribute.</summary>
/// <param name="value">The value to validate.</param>
/// <param name="validationContext">The context information about the validation operation.</param>
/// <returns>An instance of the <see cref="System.ComponentModel.DataAnnotations.ValidationResult"></see> class.</returns>
protected virtual ValidationResult IsValid(
object value,
ValidationContext validationContext); /// <summary>Validates the specified object.</summary>
/// <param name="value">The object to validate.</param>
/// <param name="validationContext">The <see cref="T:System.ComponentModel.DataAnnotations.ValidationContext"></see> object that describes the context where the validation checks are performed. This parameter cannot be null.</param>
/// <exception cref="T:System.ComponentModel.DataAnnotations.ValidationException">Validation failed.</exception>
public void Validate(object value, ValidationContext validationContext); /// <summary>Validates the specified object.</summary>
/// <param name="value">The value of the object to validate.</param>
/// <param name="name">The name to include in the error message.</param>
/// <exception cref="T:System.ComponentModel.DataAnnotations.ValidationException"><paramref name="value">value</paramref> is not valid.</exception>
public void Validate(object value, string name);
}
  • 常用数据验证

    • RequiredAttribute
    • RegularExpressionAttribute
    • CompareAttribute
    • RangeAttribute
    • MaxAttribute
    • MinAttribute
    • StringLengthAttribute
    • DataTypeAttribute
  • 服务器端使用

    • 使用包含验证规则的类接收数据
    • 使用ModelState.IsValid判断是否符合要求
  • 前端使用

    • 定义强类型视图并传递包含验证规则的业务数据模型
    • 使用HtmlHelper.ValidationFor初始前端验证规则
    • 使用HtmlHelper.ValidationMessageFor生成提示文字

public class UserLogin
{
[Required(ErrorMessage = "用户名不能为空")]
[StringLength(10,ErrorMessage = "用户名长度不能超过10位")]
public string UserName { get; set; } //[Required(ErrorMessage = "密码不能为空")]
[StringLength(6,ErrorMessage = "密码长度不能超过6位")]
public string Password { get; set; }
}
    public class FormController : Controller
{
public IActionResult Index()
{
return View(new UserLogin());
} public IActionResult PostData(UserLogin login)
{
return Content(ModelState.IsValid?"数据有效":"数据无效");
}
}
@model Lesson2.Models.UserLogin
@{
Layout = null;
} <!DOCTYPE html> <html>
<head>
<meta name="viewport" content="width=device-width" />
<title>Index</title>
<script src="~/lib/jquery/dist/jquery.min.js"></script>
<script src="~/lib/jquery-validation/dist/jquery.validate.min.js"></script>
<script src="~/lib/jquery-validation-unobtrusive/jquery.validate.unobtrusive.min.js"></script>
</head>
<body>
<form asp-action="PostData" method="post">
<table>
<tr>
<td>用户名</td>
<td>@Html.TextBoxFor(m => m.UserName)</td>
<td>@Html.ValidationMessageFor(m => m.UserName)</td>
</tr>
<tr>
<td>密码</td>
<td>@Html.PasswordFor(m => m.Password)</td>
<td>@Html.ValidationMessageFor(m => m.Password)</td>
</tr>
<tr>
<td></td>
<td><input type="submit" value="登录" /></td>
<td></td>
</tr>
</table>
</form>
</body>
</html>

第五课 路由规则

  • 路由

    • 定义用户请求与控制器方法之前的映射关系
  • 路由配置

    • IRouteBuilder
      • 通过MapRoute方法配置路由模板
    app.UseMvc(routes =>
{
routes.MapRoute(
name: "default",
template: "{controller=Home}/{action=Index}/{id?}"); routes.MapRoute(
name: "admin_default",
template: "admin/{controller=Home}/{action=Index}/{id?}");
});
  • RouteAttribute
    • 应用在控制器及方法上
    • 通过Template属性配置路由模板
    [Route("admin/form")]
public class FormController : Controller
{
[Route("index")]
public IActionResult Index()
{
return View(new UserLogin());
} public IActionResult PostData(UserLogin login)
{
return Content(ModelState.IsValid?"数据有效":"数据无效");
}
}
  • 路由约束
    • 对路由数据进行约束
    • 只有约束满足条件才能匹配成功
约束 示例 说明
required "Product/{ProductName:required}" 参数必选
alpha "Product/{ProductName:alpha}" 匹配字母,大小写不限
int "Product/{ProductId:int}" 匹配int类型
··· ··· ···
composite "Product/{ProductId:composite}" 匹配composite类型
length "Product/{ProductName:length(5)}" 长度必须是5个字符
length "Product/{ProductName:length(5)}" 长度在5-10之间
maxlength "Product/{ProductId:maxlength(10)}" 最大长度为10
minlength "Product/{ProductId:minlength(3)}" 最小长度为3
min "Product/{ProductId:min(3)}" 大于等于3
max "Product/{ProductId:max(10)}" 小于等于10
range "Product/{ProductId:range(5,10)}" 对应的数组在5-10之间
regex "Product/{ProductId:regex(^\d{4}$)}" 符合指定的正则表达式
  • 路由数据
    • 路由数据也是请求数据的一部分
    • 路由数据与表单数据一样,也可以绑定到参数上
    • 默认是通过名称进行匹配,也可以通过FormRouteAttribute匹配参数与路由数据的映射关系
    public IActionResult Index([FromRoute] int? id)
{
return View();
}

第六课 应用发布与部署

  • 发布
    • 发布方法
      • 使用Visual Studio发布应用:项目右键 -> 发布 -> 发布方式选择...
      • 使用dotnet publish命令行工具发布:dotnet publish --configuration Release --runtime win7-x64 --output c:\svc
  • 视图预编译
    • 少了运行时编译过程,启动速度快
    • 预编译后,整个程序包更小
    • 可以通过MvcRazorCompileOnPublish配置是否开启,默认是开启状态
      • 关闭视图预编译:
        • 打开项目的.csproj文件
        • 配置MvcRazorCompileOnPublishfalse
<Project Sdk="Microsoft.NET.Sdk.Web">

  <PropertyGroup>
<TargetFramework>netcoreapp2.1</TargetFramework>
<!-- 关闭视图预编译 -->
<MvcRazorCompileOnPublish>false</MvcRazorCompileOnPublish>
</PropertyGroup> <ItemGroup>
<PackageReference Include="Microsoft.AspNetCore.App" />
<PackageReference Include="Microsoft.AspNetCore.Razor.Design" Version="2.1.2" PrivateAssets="All" />
<PackageReference Include="Microsoft.VisualStudio.Web.CodeGeneration.Design" Version="2.1.1" />
</ItemGroup> </Project>
<!-- 依赖框架的部署 (FDD) -->
<PropertyGroup>
<TargetFramework>netcoreapp2.2</TargetFramework>
<RuntimeIdentifier>win7-x64</RuntimeIdentifier>
<SelfContained>false</SelfContained>
<IsTransformWebConfigDisabled>true</IsTransformWebConfigDisabled>
</PropertyGroup>
<!-- 独立部署 (SCD) -->
<PropertyGroup>
<TargetFramework>netcoreapp2.2</TargetFramework>
<RuntimeIdentifier>win7-x64</RuntimeIdentifier>
<IsTransformWebConfigDisabled>true</IsTransformWebConfigDisabled>
</PropertyGroup>
...
...
...

源码地址

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