在ASP.NET Core中存储大量图像文件，可以使用Amazon S3存储服务。以下是一个示例解决方法：

1. 首先，安装必要的NuGet包：AWSSDK.S3和Microsoft.AspNetCore.Http。

2. 在appsettings.json文件中添加Amazon S3的凭证信息和桶名称：

{
  "AWS": {
    "AccessKey": "YOUR_ACCESS_KEY",
    "SecretKey": "YOUR_SECRET_KEY",
    "BucketName": "YOUR_BUCKET_NAME"
  }
}

3. 创建一个S3Service类，用于连接到Amazon S3并执行文件上传和删除操作：

using Amazon.S3;
using Amazon.S3.Model;
using Microsoft.AspNetCore.Http;
using Microsoft.Extensions.Configuration;
using System.IO;
using System.Threading.Tasks;

public class S3Service
{
    private readonly IConfiguration _configuration;
    private readonly string _bucketName;
    private readonly IAmazonS3 _s3Client;

    public S3Service(IConfiguration configuration, IAmazonS3 s3Client)
    {
        _configuration = configuration;
        _bucketName = _configuration["AWS:BucketName"];
        _s3Client = s3Client;
    }

    public async Task UploadFileAsync(IFormFile file)
    {
        using (var memoryStream = new MemoryStream())
        {
            await file.CopyToAsync(memoryStream);
            var uploadRequest = new PutObjectRequest
            {
                BucketName = _bucketName,
                Key = file.FileName,
                InputStream = memoryStream,
                ContentType = file.ContentType
            };
            await _s3Client.PutObjectAsync(uploadRequest);
            return file.FileName;
        }
    }

    public async Task DeleteFileAsync(string fileName)
    {
        var deleteRequest = new DeleteObjectRequest
        {
            BucketName = _bucketName,
            Key = fileName
        };
        await _s3Client.DeleteObjectAsync(deleteRequest);
    }
}

4. 在Startup.cs文件中进行配置：

using Amazon.S3;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Hosting;

public class Startup
{
    public Startup(IConfiguration configuration)
    {
        Configuration = configuration;
    }

    public IConfiguration Configuration { get; }

    public void ConfigureServices(IServiceCollection services)
    {
        services.AddControllers();

        services.AddAWSService();
        services.AddScoped();
    }

    public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
    {
        if (env.IsDevelopment())
        {
            app.UseDeveloperExceptionPage();
        }

        app.UseRouting();

        app.UseEndpoints(endpoints =>
        {
            endpoints.MapControllers();
        });
    }
}

5. 创建一个API控制器来处理图像上传和删除的请求：

using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using System.Threading.Tasks;

[ApiController]
[Route("api/images")]
public class ImagesController : ControllerBase
{
    private readonly S3Service _s3Service;

    public ImagesController(S3Service s3Service)
    {
        _s3Service = s3Service;
    }

    [HttpPost]
    public async Task UploadImage(IFormFile file)
    {
        var fileName = await _s3Service.UploadFileAsync(file);
        return Ok(fileName);
    }

    [HttpDelete("{fileName}")]
    public async Task DeleteImage(string fileName)
    {
        await _s3Service.DeleteFileAsync(fileName);
        return NoContent();
    }
}

现在，你可以使用UploadImage方法来上传图像文件，并使用DeleteImage方法来删除图像文件。

注意：请确保您已正确配置AWS凭证信息和桶名称，并具有足够的权限访问Amazon S3服务。此外，还需要根据需要进行错误处理和验证。