nlog richtextbox - Target cannot be found: 'RichTextBox'

Question

I had this working, but I tried to update nlog and use the nuget packages, including NLog.Windows.Forms.

Now I am getting NLog.NLogConfigurationException with the inner exception:

Target cannot be found: 'RichTextBox'

The project references both: NLog and NLog.Windows.Forms

from packages.config:

  <package id="NLog" version="4.3.4" targetFramework="net46" />
  <package id="NLog.Config" version="4.3.4" targetFramework="net46" />
  <package id="NLog.Schema" version="4.3.4" targetFramework="net46" />
  <package id="NLog.Windows.Forms" version="4.2.3" targetFramework="net46" />

from nlog.config

<target name="rtb" xsi:type="RichTextBox" controlName="RichTextBox1" formName="NewForm"
        useDefaultRowColoringRules="true" layout="[${date}] [${level:uppercase=true}] [${logger}] ${message}" />

...

<logger name="*" minlevel="Trace" writeTo="file,rtb" />

Adding internal logging didn't seem to give much more information:

...
...
2016-06-03 06:17:23.9385 Trace Scanning MessageLayoutRenderer 'Layout Renderer: ${message}'
2016-06-03 06:17:23.9550 Info Adding target File Target[file]
2016-06-03 06:17:23.9550 Debug Registering target file: NLog.Targets.FileTarget
2016-06-03 06:17:23.9550 Error Error in Parsing Configuration File. Exception: NLog.NLogConfigurationException: Exception occurred when loading configuration from C:\Users\Derek.Morin\Documents\Visual Studio 2010\Projects\ScriptCode\ScriptCode.ConvertedToC#\bin\x86\Debug\NLog.config ---> System.ArgumentException: Target cannot be found: 'RichTextBox'
   at NLog.Config.Factory`2.CreateInstance(String name)
   at NLog.Config.XmlLoggingConfiguration.ParseTargetsElement(NLogXmlElement targetsElement)
   at NLog.Config.XmlLoggingConfiguration.ParseNLogElement(NLogXmlElement nlogElement, String filePath, Boolean autoReloadDefault)
   at NLog.Config.XmlLoggingConfiguration.ParseTopLevel(NLogXmlElement content, String filePath, Boolean autoReloadDefault)
   at NLog.Config.XmlLoggingConfiguration.Initialize(XmlReader reader, String fileName, Boolean ignoreErrors)
   --- End of inner exception stack trace ---
2016-06-03 06:17:23.9700 Error Error has been raised. Exception: System.ArgumentException: Target cannot be found: 'RichTextBox'
   at NLog.Config.Factory`2.CreateInstance(String name)
   at NLog.Config.XmlLoggingConfiguration.ParseTargetsElement(NLogXmlElement targetsElement)
   at NLog.Config.XmlLoggingConfiguration.ParseNLogElement(NLogXmlElement nlogElement, String filePath, Boolean autoReloadDefault)
   at NLog.Config.XmlLoggingConfiguration.ParseTopLevel(NLogXmlElement content, String filePath, Boolean autoReloadDefault)
   at NLog.Config.XmlLoggingConfiguration.Initialize(XmlReader reader, String fileName, Boolean ignoreErrors)

If I can't get an answer for how to get it working with the nlog.config file, at least I found the following workaround:

I adapted the answer from here: ( I didn't like the colouring choices )

Display NLog trace in RichTextBox

   private void SetupRichTextBoxLogger()
   {
      NLog.Windows.Forms.RichTextBoxTarget target = new NLog.Windows.Forms.RichTextBoxTarget();
      target.Name = "RichTextBox";
      target.Layout = "${longdate} ${level:uppercase=true} ${logger} ${message}";
      target.ControlName = nameof(this.RichTextBox1);
      target.FormName = nameof(NewForm);
      target.AutoScroll = true;
      target.MaxLines = 0;
      target.UseDefaultRowColoringRules = true;
      AsyncTargetWrapper asyncWrapper = new AsyncTargetWrapper();
      asyncWrapper.Name = "AsyncRichTextBox";
      asyncWrapper.WrappedTarget = target;

      SimpleConfigurator.ConfigureForTargetLogging( asyncWrapper, LogLevel.Trace );
   }

Did you checked the [Internal log](https://github.com/NLog/NLog/wiki/Internal-Logging)? — Julian, Jun 03 '16 at 06:23
Please post an issue on Github: https://github.com/NLog/NLog.Windows.Forms/issues — Julian, Jun 03 '16 at 11:51
Ok. I did. https://github.com/NLog/NLog.Windows.Forms/issues/31 — Derek, Jun 03 '16 at 12:32

Rolf Kristensen · Answer 1 · 2022-06-07T18:02:24.823

1

Besides having the nuget-package NLog.Windows.Forms installed (Remember to use v4.6 or newer, together with NLog 5.0)

Then it is also recommended to update NLog.config to include NLog.Windows.Forms-assembly in <extensions>:

<?xml version="1.0" encoding="utf-8" ?>
<nlog>
  <extensions> 
    <add assembly="NLog.Windows.Forms"/> 
  </extensions> 

  ...
</nlog>

edited Jun 07 '22 at 18:02

answered Apr 08 '22 at 11:14

Rolf Kristensen

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score 0 · Answer 2 · answered Jun 07 '22 at 16:04

0

FWIW, I had this problem after upgrading to NLog 5 and removing the deprecated NLog.Config. Upon reverting to 4.7.15 with NLog.Config, the problem no longer occurred.

In my case, having NLog.Windows.Forms installed did not help.

answered Jun 07 '22 at 16:04

Nick

1

[NLog.Windows.Forms](https://www.nuget.org/packages/NLog.Windows.Forms/) v4.6 should work just fine with NLog 5.0. You are wellcome to create an issue at https://github.com/NLog/NLog.Windows.Forms where you provide the `NLog.config` and the output from the [NLog InternalLogger](https://github.com/NLog/NLog/wiki/Internal-Logging) at Debug-Level. – Rolf Kristensen Jun 07 '22 at 18:00

nlog richtextbox - Target cannot be found: 'RichTextBox'

2 Answers2