除了dbContext之外，如何在Blazor中向服务添加参数

Question

VS2022 NetCore 6 EF 6

builder.Services.AddDbContext<MyAppDbContext>(options removed for simplicity)
//This is my service registered on Program.cs:
builder.Services.AddScoped<AccountService>();

//This is the existing class that works as expected:
public class AccountService
{
private readonly MyAppDbContext _context;  
public AccountService(MyAppDbContext context)
{
_context = context;
}
}
//So far so good... 

// Now I need to add another parameter to the service:
public class AccountService
{
private readonly MyAppDbContext _context;  
public AccountService(MyAppDbContext context, string newParameter)
{
_context = context;
string temp = newParameter;
}
}

// But I cannot register; I don't know what to put as first value and if I put MyAppDbContext it gives an error saying it is a type.

builder.Services.AddScoped(ServiceProvider => { return new AccountService(??, newParameter);});
// This works (no compile error) for newParameter but ignores DbContext
builder.Services.AddScoped(ServiceProvider => { return new AccountService( **null**, newParameter);});

Answer 1

您的注册将变得更丑陋：

builder.Services.AddScoped<AccountService>(x => new AccountService( 
x.GetRequiredService<MyAppDbContext>(),
newParameter));

每次需要AccountService时，让ServiceProvider创建(作用域(DbContext是很重要的。