This project is licensed under the terms of the Apache license 2.0.

Using ElmahCore

ELMAH for Net.Standard and Net.Core

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Add nuget package elmahcore

Simple usage


1)    services.AddElmah() in ConfigureServices 
2)    app.UseElmah(); in Configure

app.UseElmah() must be after initializing other exception handling middleware, such as (UseExceptionHandler, UseDeveloperExceptionPage, etc.)

Default elmah path ~/elmah.

Change URL path

services.AddElmah(options => options.Path = "you_path_here")

Restrict access to the Elmah url

services.AddElmah(options =>
        options.OnPermissionCheck = context => context.User.Identity.IsAuthenticated;

Note: app.UseElmah(); needs to be after


or the user will be redirected to the sign in screen even if he is authenticated.

Change Error Log type

You can create your own error log, which will store errors anywhere.

    class MyErrorLog: ErrorLog
    //implement ErrorLog

This ErrorLogs available in board:

  • MemoryErrorLog – store errors in memory (by default)
  • XmlFileErrorLog – store errors in XML files
  • SqlErrorLog - store errors in MS SQL (add reference to ElmahCore.Sql)
  • MysqlErrorLog - store errors in MySQL (add reference to ElmahCore.MySql)
  • PgsqlErrorLog - store errors in PostgreSQL (add reference to ElmahCore.Postgresql)
    services.AddElmah<XmlFileErrorLog>(options =>
     options.LogPath = "~/log"; // OR options.LogPath = "с:\errors";
    services.AddElmah<SqlErrorLog>(options =>
     options.ConnectionString = "connection_string";
     options.SqlServerDatabaseSchemaName = "Errors"; //Defaults to dbo if not set
     options.SqlServerDatabaseTableName = "ElmahError"; //Defaults to ELMAH_Error if not set

    Rise exception

    public IActionResult Test()
     HttpContext.RiseError(new InvalidOperationException("Test"));

    Microsoft.Extensions.Logging support

    Since version 2.0 ElmahCore support Microsoft.Extensions.Logging alt text

Source Preview

Since version 2.0.1 ElmahCore support source preview. Just add paths to source files.

services.AddElmah(options =>
   options.SourcePaths = new []

Log the request body

Since version 2.0.5 ElmahCore can log the request body.

Logging SQL request body

Since version 2.0.6 ElmahCore can log the SQL request body. alt text

Logging method parameters

Since version 2.0.6 ElmahCore can log method parameters. alt text

using ElmahCore;

public void TestMethod(string p1, int p2)
    // Logging method parameters
    this.LogParams((nameof(p1), p1), (nameof(p2), p2));

Using UseElmahExceptionPage

You can replace UseDeveloperExceptionPage to UseElmahExceptionPage

if (env.IsDevelopment())

Using Notifiers

You can create your own notifiers by implement IErrorNotifier interface and add notifier to Elmah options:

services.AddElmah<XmlFileErrorLog>(options =>
    options.Path = @"errors";
    options.LogPath = "~/logs";
    options.Notifiers.Add(new ErrorMailNotifier("Email",emailOptions));

Each notifier must have unique name.

Using Filters

You can use Elmah XML filter configuration in separate file, create and add custom filters:

services.AddElmah<XmlFileErrorLog>(options =>
    options.FiltersConfig = "elmah.xml";
    options.Filters.Add(new MyFilter());

Custom filter must implement IErrorFilter. XML filter config example:

<?xml version="1.0" encoding="utf-8" ?>
            <notifier name="Email"/>
                <greater binding="HttpStatusCode" value="399" type="Int32" />
                <lesser  binding="HttpStatusCode" value="500" type="Int32" />

see more here

JavaScript filters not yet impemented :(

Add notifiers to errorFilter node if you do not want to send notifications Filtered errors will be logged, but will not be sent.


ELMAH for Net.Standard and Net.Core

Elmahcore Info

⭐ Stars194
🔗 Source
🕒 Last Update10 months ago
🕒 Created5 years ago
🐞 Open Issues51
➗ Star-Issue Ratio4
😎 AuthorElmahCore