In ErrorLog we need to keep track of the File and the Function details where this Exception occurs. So, instead of sending the Hardcoded Values (i.e : Function Name , File Name ) to ErrorLog, we can directly get this details from Exception object (i.e : Exception ex) as follows :

Use namespace :

using System.Diagnostics;
using System.Reflection;
using System.Data;

Function where Error Occurred :

/// <summary>
/// Get country names
/// </summary>
public void GetCountryNames()
{
    try
    {
        CountryClass Country = new CountryClass();
        DataTable dtCountry = new DataTable();
        dtCountry = country.GetCountryList();
        ddlCountry.DataSource = dtCountry;
        ddlCountry.DataTextField = "Name";
        ddlCountry.DataValueField = "Id";
        ddlCountry.DataBind();
        ddlCountry.Items.Insert(0. newListItem(_strSelect,              "0"));
    }
    catch (Exception ex)
    {
        //call ErrorLog using the File Details
        LogError(ex);
    }

    finally
    {
        country = null;
        dtCountry = null;
    }
}

 ErrorLog Function accepts Exception object as Parameter :

/// <summary>
  /// Logs the exception.
  /// </summary>
  /// <param name="ex"></param>
  public static void LogError(Exception ex)
  {

      // Get the File Details from Exception
      StackTrace st = new StackTrace(ex);

 

      // Get the object of MethodBase from StackTrace
      MethodBase mb = st.GetFrame(st.FrameCount - 1).GetMethod();

 

      // Get FileName with NameSpace
      string source = mb.DeclaringType.FullName;

 

      // Get Function Name
      string methodName = mb.Name;

 

      //Implement ErrorLog Logics here using the File Details
      //AddLogError(source, ex, methodName);


  }