EF Core: Get the exact fields causing the issue "string or binary data would be truncated"

EvilFields.cs

//Usage

public class TestController : Controller
{
    private readonly IMyContext _context;
    public TestController(IMyContext context)
    {
      _context = context;
    }
    
    public async Task<string> Post(Record record)
    {
        try
        {
          record.FirstName = "i am a longer name than the db field is expecting!";
          await _context.Records.AddAsync(record);          
          await _context.SaveChangesAsync();
        }
        catch(Exception ex)
        {
           // DbUpdateException
           
            var fields = _context.GetEvilFields("Records", record);
            
            // you will get all the fields which has values greater than db field length
        }
    }
}

// Implentation
public interface IMyContext
{
  DbSet<Record> Records { get;set; }  
  
  Task<int> SaveChangesAsync();
  Dictionary<string, string> GetEvilFields(string tableName, object instance);
}

public class MyContext: DbContext, IMyContext
{
    public DbSet<Record> Records { get;set; }
    
    
    public Dictionary<string, string> GetEvilFields(string tableName, object instance)
    {
        Dictionary<string, string> result = new Dictionary<string, string>();

        var tableType = this.Model.GetEntityTypes().First(c => c.GetTableName().Contains(tableName));

        if (tableType != null)
        {
           int i = 0;

           foreach (var property in tableType.GetProperties())
           {
               var maxlength = property.GetMaxLength();
               var prop = instance.GetType().GetProperties().FirstOrDefault(_ => _.Name == property.Name);

               if (prop != null)
               {
                   var length = prop.GetValue(instance)?.ToString()?.Length;

                   if (length > maxlength)
                   {
                        result.Add($"{i}.Evil.Property", prop.Name);
                        result.Add($"{i}.Evil.Value", prop.GetValue(instance)?.ToString());
                        result.Add($"{i}.Evil.Value.Length", length?.ToString());
                        result.Add($"{i}.Evil.Db.MaxLength", maxlength?.ToString());
                        i++;
                    }
               }
            }
       }

       return result;
    }
}

Your line 48, i.e. this.Model.GetEntityTypes() and 56, i.e. property.GetMaxLength(); don't seem to be available in EF 6.
Can you suggest an alternative?

And one more question:
Does tableType.GetProperties() come directly from Database, for eg: varchar(10) defined in database table?
OR are these properties coming from Database table model fields defined in our code? For eg:
[Column("SomeColumnName", TypeName="varchar(10)")] // This is what I annotated the field with
public string SomeColumnName { get; set; }

Hi @affableashish , i haven't tested it with EF6 yet and tableType.GetProperties() comes directly from database.