ASP.NET Core (.Net 6) Web 应用程序在作为服务运行时抛出 System.NotSupportedException。（服务不会启动）

Question

当我尝试将 .Net Web 应用程序作为 Windows 服务运行时，它无法启动。如果我只运行可执行文件，它会起作用，但在尝试作为服务运行时会神秘地失败。我已记录相关错误消息并在下面报告了我的解决方案。

事件查看器中出现以下异常。

事件查看器中的异常

应用程序：WebApplication5.exe CoreCLR 版本：6.0.222.6406 .NET 版本：6.0.2 说明：由于未处理的异常，进程被终止。异常信息：System.NotSupportedException：内容根目录从“C:\Windows\system32”更改为“C:\Program Files (x86)\My Company\webapp5”。不支持使用 WebApplicationBuilder.Host 更改主机配置。请改用 WebApplication.CreateBuilder(WebApplicationOptions)。在 Microsoft.AspNetCore.Builder.ConfigureHostBuilder.ConfigureHostConfiguration(操作1 configureDelegate) at Microsoft.Extensions.Hosting.HostingHostBuilderExtensions.UseContentRoot(IHostBuilder hostBuilder, String contentRoot) at Microsoft.Extensions.Hosting.WindowsServiceLifetimeHostBuilderExtensions.UseWindowsService(IHostBuilder hostBuilder, Action1 配置) 在 Microsoft.Extensions.Hosting.WindowsServiceLifetimeHostBuilderExtensions.UseWindowsService(IHostBuilder hostBuilder) 在 Program.$(String[] args) 在 C:\Users\Jonathan\source\repos \WebApplication5\WebApplication5\Program.cs：第 10 行

重新创建的步骤

程序.cs

我的应用程序基于ASP.NET Core Web API模板。我按照https://learn.microsoft.com/en-us/aspnet/core/host-and-deploy/windows-service?view=aspnetcore-6.0&tabs=visual-studio#app-configuration上的说明进行操作并添加UseWindowsService()到Program.cs

var builder = WebApplication.CreateBuilder(args);

// Add services to the container.

builder.Services.AddControllers();
// Learn more about configuring Swagger/OpenAPI at https://aka.ms/aspnetcore/swashbuckle
builder.Services.AddEndpointsApiExplorer();
builder.Services.AddSwaggerGen();

builder.Host.UseWindowsService();

var app = builder.Build();

// Configure the HTTP request pipeline.
if (app.Environment.IsDevelopment())
{
    app.UseSwagger();
    app.UseSwaggerUI();
}

app.UseHttpsRedirection();

app.UseAuthorization();

app.MapControllers();

app.Run();

部署二进制文件并创建服务

我编译一个二进制文件dotnet publish -c Debug --self-contained --runtime win-x64 -p:PublishSingleFile=true

将输出复制到目标计算机并在管理 Powershell 中运行

New-Service -Name WebApplication5 -BinaryPathName C:\Users\WDAGUtilityAccount\Desktop\webapp5\WebApplication5.exe

当我尝试启动服务时：

    PS C:> Start-Service WebApp5
    Start-Service : Service 'WebApp5 (WebApp5)' cannot be started due to the following error: Cannot start service WebApp5 on computer '.'.
    At line:1 char:1
    + Start-Service WebApp5
    + ~~~~~~~~~~~~~~~~~~~~~
        + CategoryInfo          : OpenError: (System.ServiceProcess.ServiceController:ServiceController) [Start-Service], ServiceCommandException
        + FullyQualifiedErrorId : CouldNotStartService,Microsoft.PowerShell.Commands.StartServiceCommand

当我使用服务 GUI 时：

Windows 无法在本地计算机上启动 WebApplication5 服务

错误1053：服务没有及时响应启动或控制请求。

Answer 1

就像事件查看器中的异常所示，我需要使用非默认构造函数Program.cs并在那里设置ContentRootPath。

更改此默认构造函数：

var builder = WebApplication.CreateBuilder(args);

改成：

var webApplicationOptions = new WebApplicationOptions
{
    ContentRootPath = AppContext.BaseDirectory,
    Args = args,
};    
var builder = WebApplication.CreateBuilder(webApplicationOptions);

这是我的其余部分program.cs供参考：

//set ContentRootPath so that builder.Host.UseWindowsService() doesn't crash when running as a service
var webApplicationOptions = new WebApplicationOptions
{
    ContentRootPath = AppContext.BaseDirectory,
    Args = args,
};    
var builder = WebApplication.CreateBuilder(webApplicationOptions);

//All the following code is unchanged from my original program.cs

// Add services to the container.

builder.Services.AddControllers();
// Learn more about configuring Swagger/OpenAPI at https://aka.ms/aspnetcore/swashbuckle
builder.Services.AddEndpointsApiExplorer();
builder.Services.AddSwaggerGen();

builder.Host.UseWindowsService();

var app = builder.Build();

// Configure the HTTP request pipeline.
if (app.Environment.IsDevelopment())
{
    app.UseSwagger();
    app.UseSwaggerUI();
}

app.UseHttpsRedirection();

app.UseAuthorization();

app.MapControllers();

app.Run();