Question

在执行此代码时，阅读器显示“枚举未产生结果”，方法返回空模型。我不知道出了什么问题

 public UserModel GetUser(string email)
    {
        email = email.ToString();
        var connection = OpenConnection();
        var command = connection.CreateCommand();
        command.CommandText = "select * from Users where UserName = @email;";
        AddParameterString(command, "@email", email);
        SqlDataReader reader = command.ExecuteReader();
        UserModel model = new UserModel();
        while (reader.Read())
        {
            model.ConfirmedEmail = Convert.ToBoolean(reader["ConfirmedEmail"]);
            model.UserId = int.Parse(reader["userId"].ToString());
            model.UserName = reader["UserName"].ToString();
            model.UserEmail = reader["UserEmail"].ToString();
            model.PasswordHash = reader["PasswordHash"].ToString();
            model.PasswordSalt = reader["PasswordSalt"].ToString();
            model.UserRole = reader["UserRole"].ToString();
        }
        return model;
    }
}



 protected void AddParameterString(SqlCommand command, string parameterName, string value)
    {
        var newParameter = command.CreateParameter();
        newParameter.ParameterName = parameterName;
        newParameter.DbType = System.Data.DbType.String;
        newParameter.Value = value;
        command.Parameters.Add(newParameter);
    }

Answer 1

命名参数时不需要@符号（请参阅：http://www.dotnetperls.com/sqlparameter）

AddParameterString(command, "email", email);

Answer 2

AddParameterString（命令，＆＃34; @ email＆＃34;，email）; //删除此行

command.Parameters.AddWithValue（＆＃34; @ email＆＃34;，email）; //添加此行

SqlDataReader - 枚举没有产生任何结果

2 个答案: