How to get the method name and line number in Exception in ASP Core 5 - asp.net-core

Question

I want to get the method name and line number when an error occur, I am using Core 5.
try
{
//My code
}
catch (Exception ex)
{
_logger.LogError(ex, "Method Name / Line Number");
}
Update:
I found a Solution like this:
_logger.LogError(ex, "\n=> ex Error: " + ex + "\n=> Action Name: " + ex.TargetSite.ReflectedType.Name + "\n=> Error Message: " + ex.Message + "\n=> Line Number: " + ex.LineNumber());

Answer 1

A simple call to ToString() on exception will give you the complete information needed. For example when we run the following code:
public static void Main()
{
try
{
//my code
throw new ArgumentException();
}
catch (Exception ex)
{
Console.WriteLine(ex.ToString());
}
}
The output would be somewhat like:
System.ArgumentException: Value does not fall within the expected range.
at ConsoleApp.Program.Main() in C:\Users\USER\source\Playground\ConsoleApp1\Program.cs:line 20
where Main() is the method name and 20 is the line number.
To get the format as required in question we can write a wrapper around the exception and fetch the line number from it:
using System;
using System.Reflection;
namespace ConsoleApp
{
class Program
{
public static void Main()
{
try
{
//my code
throw new ArgumentException();
}
catch (Exception ex)
{
Console.WriteLine(MethodBase.GetCurrentMethod().Name + "/" + GetLineNumber(ex));
}
}
public static int GetLineNumber(Exception ex)
{
var lineNumber = 0;
const string lineSearch = ":line ";
var index = ex.StackTrace.LastIndexOf(lineSearch);
if (index != -1)
{
var lineNumberText = ex.StackTrace.Substring(index + lineSearch.Length);
if (int.TryParse(lineNumberText, out lineNumber))
{
}
}
return lineNumber;
}
}
}
Note: In the extract line method, we are fetching the top most exception. This comes in handy when we have a chain of exceptions in our stack trace.