将Abp移植进.NET MAUI项目（二）：配置与基类编写
因为我们要做一个数据持久化型的小应用，所以在完成Abp功能的集成后，我们需要做数据库相关的配置工作
配置数据库
在MauiBoilerplate.Core项目中，添加两个实体类：
我们简单的写一个歌曲（song）的实体类
其中包含了歌曲标题（MusicTitle），艺术家（Artist），专辑（Album），时长（Duration）以及发售日期（ReleaseDate）
public class Song : FullAuditedEntity<long>
{
[Key, DatabaseGenerated(DatabaseGeneratedOption.Identity)]
public override long Id { get; set; }
public string MusicTitle { get; set; }
public string Artist { get; set; }
public string Album { get; set; }
public TimeSpan Duration { get; set; }
public DateTime ReleaseDate { get; set; }
}
在MauiBoilerplate.EntityFrameworkCore项目中：将这个类添加至MauiBoilerplateDbContext中
public class MauiBoilerplateDbContext : AbpDbContext
{
//Add DbSet properties for your entities...
public DbSet<Song> Song { get; set; }
}新建WithDbContextHelper.cs
创建一个静态类WithDbContext，利用Abp的工作单元模式对dbcontext执行操作
public class WithDbContextHelper
{
public static void WithDbContext<TDbContext>(IIocResolver iocResolver, Action<TDbContext> contextAction)
where TDbContext : DbContext
{
using (var uowManager = iocResolver.ResolveAsDisposable<IUnitOfWorkManager>())
{
using (var uow = uowManager.Object.Begin(TransactionScopeOption.Suppress))
{
var context = uowManager.Object.Current.GetDbContext<TDbContext>();
contextAction(context);
uow.Complete();
}
}
}
}
[可选]种子数据相关类编写
编写种子数据帮助类SeedHelper.cs，与数据库初始化类InitialDbBuilder，这里将在程序启动时向数据库插入一些种子数据
public static class SeedHelper
{
public static void SeedHostDb(IIocResolver iocResolver)
{
Helper.WithDbContextHelper.WithDbContext<MauiBoilerplateDbContext>(iocResolver, SeedHostDb);
}
public static void SeedHostDb(MauiBoilerplateDbContext context)
{
context.SuppressAutoSetTenantId = true;
// Host seed
new InitialDbBuilder(context).Create();
}
}
编写MauiBoilerplateEntityFrameworkCoreModule.cs
[DependsOn(
typeof(MauiBoilerplateCoreModule),
typeof(AbpEntityFrameworkCoreModule))]
public class MauiBoilerplateEntityFrameworkCoreModule : AbpModule
{
public bool SkipDbContextRegistration { get; set; }
public bool SkipDbSeed { get; set; }
public override void PreInitialize()
{
if (!SkipDbContextRegistration)
{
Configuration.Modules.AbpEfCore().AddDbContext<MauiBoilerplateDbContext>(options =>
{
if (options.ExistingConnection != null)
{
DbContextOptionsConfigurer.Configure(options.DbContextOptions, options.ExistingConnection);
}
else
{
DbContextOptionsConfigurer.Configure(options.DbContextOptions, options.ConnectionString);
}
});
}
}
public override void Initialize()
{
IocManager.RegisterAssemblyByConvention(typeof(MauiBoilerplateEntityFrameworkCoreModule).GetAssembly());
}
public override void PostInitialize()
{
Helper.WithDbContextHelper.WithDbContext<MauiBoilerplateDbContext>(IocManager, RunMigrate);
if (!SkipDbSeed)
{
SeedHelper.SeedHostDb(IocManager);
}
}
public static void RunMigrate(MauiBoilerplateDbContext dbContext)
{
dbContext.Database.Migrate();
}
}
将MauiBoilerplate.EntityFrameworkCore设置为启动项目，选择框架为.net6.0
打开程序包管理器控制台，选择默认项目MauiBoilerplate.EntityFrameworkCore
运行Add-Migration命令，将生成迁移脚本
运行MauiBoilerplate.EntityFrameworkCore，将生成mato.db等三个文件，
编写基类（可选）
我们在使用相关的父类时，某某ContentPage，或者某某UserControl时，需要像使用AbpServiceBase一样使用一些常用的功能，比如字符串的本地化，配置，AutoMapper对象等，就像AbpServiceBase的注释里描述的那样：
/// <summary>
/// This class can be used as a base class for services.
/// It has some useful objects property-injected and has some basic methods
/// most of services may need to.
/// </summary>
此时，需要编写一个基类（奈何.net本身没有Mixin模式，C#语言也不支持多继承），这些基类仅是注入了一些常用的Manager，方便代码编写者使用，因此基类的创建不是必须的。
比如可以增加一个ContentPageBase类作为ContentPage实例控件的基类
新建ContentPageBase.cs文件，创建类ContentPageBase继承于ContentPage
public class ContentPageBase : ContentPage
{
public IObjectMapper ObjectMapper { get; set; }
/// <summary>
/// Reference to the setting manager.
/// </summary>
public ISettingManager SettingManager { get; set; }
/// <summary>
/// Reference to the localization manager.
/// </summary>
public ILocalizationManager LocalizationManager { get; set; }
/// <summary>
/// Gets/sets name of the localization source that is used in this application service.
/// It must be set in order to use <see cref="L(string)"/> and <see cref="L(string,CultureInfo)"/> methods.
/// </summary>
protected string LocalizationSourceName { get; set; }
/// <summary>
/// Gets localization source.
/// It's valid if <see cref="LocalizationSourceName"/> is set.
/// </summary>
protected ILocalizationSource LocalizationSource
{
get
{
if (LocalizationSourceName == null)
{
throw new AbpException("Must set LocalizationSourceName before, in order to get LocalizationSource");
}
if (_localizationSource == null || _localizationSource.Name != LocalizationSourceName)
{
_localizationSource = LocalizationManager.GetSource(LocalizationSourceName);
}
return _localizationSource;
}
}
private ILocalizationSource _localizationSource;
/// <summary>
/// Constructor.
/// </summary>
protected ContentPageBase()
{
LocalizationSourceName = MauiBoilerplateConsts.LocalizationSourceName;
ObjectMapper = NullObjectMapper.Instance;
LocalizationManager = NullLocalizationManager.Instance;
}
/// <summary>
/// Gets localized string for given key name and current language.
/// </summary>
/// <param name="name">Key name</param>
/// <returns>Localized string</returns>
protected virtual string L(string name)
{
return LocalizationSource.GetString(name);
}
/// <summary>
/// Gets localized string for given key name and current language with formatting strings.
/// </summary>
/// <param name="name">Key name</param>
/// <param name="args">Format arguments</param>
/// <returns>Localized string</returns>
protected virtual string L(string name, params object[] args)
{
return LocalizationSource.GetString(name, args);
}
/// <summary>
/// Gets localized string for given key name and specified culture information.
/// </summary>
/// <param name="name">Key name</param>
/// <param name="culture">culture information</param>
/// <returns>Localized string</returns>
protected virtual string L(string name, CultureInfo culture)
{
return LocalizationSource.GetString(name, culture);
}
/// <summary>
/// Gets localized string for given key name and current language with formatting strings.
/// </summary>
/// <param name="name">Key name</param>
/// <param name="culture">culture information</param>
/// <param name="args">Format arguments</param>
/// <returns>Localized string</returns>
protected virtual string L(string name, CultureInfo culture, params object[] args)
{
return LocalizationSource.GetString(name, culture, args);
}
}
同理，若我们使用了其他控件类时，可以增加一个Base类作为实例控件的基类的
比如Popup控件，就编写一个PopupBase基类。
在这里我们编写了两个基类
本地化配置
新建一个TranslateExtension.cs作为Xaml标签的本地化处理类
[ContentProperty("Text")]
public class TranslateExtension : DomainService, IMarkupExtension
{
public TranslateExtension()
{
LocalizationSourceName = MauiBoilerplateConsts.LocalizationSourceName;
}
public string Text { get; set; }
public object ProvideValue(IServiceProvider serviceProvider)
{
if (Text == null)
return "";
var translation = L(Text);
return translation;
}
}在MauiBoilerplateLocalization.cs配置好SourceFiles
public static void Configure(ILocalizationConfiguration localizationConfiguration)
{
localizationConfiguration.Sources.Add(
new DictionaryBasedLocalizationSource(MauiBoilerplateConsts.LocalizationSourceName,
new XmlEmbeddedFileLocalizationDictionaryProvider(
typeof(LocalizationConfigurer).GetAssembly(),
"MauiBoilerplate.Core.Localization.SourceFiles"
)
)
);
}编写ViewModelBase
为实现Mvvm设计模式，页面需要绑定一个继承于ViewModelBase的类型
在ViewModelBase中，需要实现INotifyPropertyChanged以处理绑定成员变化时候的通知消息；
ViewModelBase集成于AbpServiceBase以方便ViewModel代码编写者使用常用的功能，比如字符串的本地化，配置，AutoMapper对象等。
public abstract class ViewModelBase : AbpServiceBase, ISingletonDependency, INotifyPropertyChanged
{
public ViewModelBase()
{
LocalizationSourceName = MauiBoilerplateConsts.LocalizationSourceName;
}
public event PropertyChangedEventHandler PropertyChanged;
protected PropertyChangedEventHandler PropertyChangedHandler { get; }
public void VerifyPropertyName(string propertyName)
{
Type type = GetType();
if (!string.IsNullOrEmpty(propertyName) && type.GetTypeInfo().GetDeclaredProperty(propertyName) == null)
throw new ArgumentException("找不到属性", propertyName);
}
public virtual void RaisePropertyChanged([CallerMemberName] string propertyName = null)
{
PropertyChangedEventHandler propertyChanged = PropertyChanged;
if (propertyChanged == null)
return;
propertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
public virtual void RaisePropertyChanged<T>(Expression<Func<T>> propertyExpression)
{
if (PropertyChanged == null)
return;
string propertyName = GetPropertyName(propertyExpression);
if (string.IsNullOrEmpty(propertyName))
return;
RaisePropertyChanged(propertyName);
}
protected static string GetPropertyName<T>(Expression<Func<T>> propertyExpression)
{
if (propertyExpression == null)
throw new ArgumentNullException(nameof(propertyExpression));
MemberExpression body = propertyExpression.Body as MemberExpression;
if (body == null)
throw new ArgumentException("参数不合法", nameof(propertyExpression));
PropertyInfo member = body.Member as PropertyInfo;
if (member == null)
throw new ArgumentException("找不到属性", nameof(propertyExpression));
return member.Name;
}
}
至此，我们完成了数据库的配置，内容页基类与 ViewModel基类的编写，接下来可以制作我们的页面了。请看下一章将Abp移植进.NET MAUI项目（三）：构建UI层 - 林晓lx - 博客园 (cnblogs.com)
项目地址
本文来自博客园，作者：林晓lx，转载请注明原文链接：https://www.cnblogs.com/jevonsflash/p/16310391.html
