public long Run([HttpTrigger(AuthorizationLevel.Function, "get", Route = null)] HttpRequest req, ILogger log) { log.LogInformation(string.Concat("C# Calculator function started at ", DateTime.UtcNow, ".")); try { decimal response = 0; string[] fileLines = _fileOperation.ReadFileLines(); IValidateFile _validateFile = new ValidateFile(); _validateFile.ValidateFileContent(ref fileLines); IEvaluateExpression _evaluateExpression = new EvaluateExpression(); _evaluateExpression.Evaluate(ref fileLines, ref response); log.LogInformation(string.Concat("C# Calculator function completed at ", DateTime.UtcNow, ".")); return(Convert.ToInt64(response)); } catch (Exception ex) { log.LogError(string.Concat("C# Calculator function received error at ", DateTime.UtcNow, ".")); log.LogError(ex.Message, ex); throw; } }