ASP.NET Coreミドルウェアによるグローバル例外処理機構の利用について

Mvc.Filters;
Filters; using System;

namespace Log4NetWebAPI.
Controllers
    public class ExceptionFilter: IExceptionFilter
    {
        //global exception handling mechanism
        public void OnException(ExceptionContext context)
        {
            Exception ex = context;

            //The name of the controller method where the error is located
            var DisplayName = context.ActionDescriptor;

            #region The line number where the error is located line number

            The name before the line number of //// is either Chinese or English, so pay attention to the screening
            //var aaa = ex.StackTrace.Substring(ex.StackTrace.IndexOf("LineNumber"), ex.StackTrace. ;
            //var ccc = ex.StackTrace.Substring(ex.StackTrace.IndexOf("line"), ex.StackTrace.Length - ex.StackTrace.IndexOf("line& quot;));
            var lineNumber = 0;
            const string lineSearch = ":line ";
            var index = ex.StackTrace.LastIndexOf(lineSearch);
            if (index ! = -1)
            {
                var lineNumberText = ex.StackTrace.Substring(index + lineSearch.Length);
                var lineNumberStr = lineNumberText.Substring(0, lineNumberText.IndexOf("\r\n"));
                if (int.TryParse(lineNumberStr, out lineNumber))
                {

                }
            }

            #endregion

            #region Write the information to [database], here you can enter the database yourself (mongodb, SqlServer, MySQL, etc.), I'll use SqlServer as an example

            errorLog md = new errorLog();
            md.logTime = DateTime.Now;
            md.logType = "error";
            md.displayName = DisplayName; // error location
            md.lineNumber = lineNumber; // error line number
            md.message = ex.Message; //error message
            md.messagedetails = ex.ToString(); //error details
            md.createTime = DateTime.Now;

            using (var ctx = new dbContext())
            {

                ctx.Add(md);
                ctx.SaveChanges();
            }
            #endregion

            // Here's a hint of what your return page will show, omitted below

        }
    }
}

// このメソッドはランタイムから呼び出されます。コンテナにサービスを追加するには、このメソッドを使用します。
        public void ConfigureServices(IServiceCollection services)
        サービス
            services.AddControllers()。

            // グローバルな例外処理機構を追加する
            services.AddMvc(option => {)
                option.Filters.Add<ExceptionFilter>();
            });
        }