如何从Datareader获取多行

Question

这是我的代码.它工作正常,但只返回一行.正如您在SQL语句中看到的,我需要在表单中使用的数据网格中返回2行.虽然该过程读取2行,但它只显示一行.NameAddrmark是字段的构造函数.

    public NameAddrmark GetNameRespCommentData(string respid)
    {
        NameAddrmark cms = new NameAddrmark();
        //var cms = new List<NameAddrmark>();

        SqlConnection connection = new SqlConnection(GeneralData.getConnectionString());

        string sql = "SELECT top 2 * FROM dbo.RESPONDENT_COMMENT WHERE respid = " + GeneralData.AddSqlQuotes(respid) + " and USRNME = " + GeneralData.AddSqlQuotes(UserInfo.UserName) + " order by COMMDATE ASC";
        SqlCommand command = new SqlCommand(sql, connection);

        try
        {
            connection.Open();
            SqlDataReader reader = command.ExecuteReader(CommandBehavior.SingleResult);

            while(reader.Read())
            //if (reader.Read())
            {
                cms.Id = respid;
                cms.Date8 = reader["COMMDATE"].ToString();
                cms.Usrnme = reader["USRNME"].ToString();
                cms.Marktext = reader["COMMTEXT"].ToString();
            }
            //else
            //    cms = null;
        }
        catch (SqlException ex)
        {
            throw ex;
        }
        finally
        {
            connection.Close();
        }
        return cms;
    }

在我的表单上,我将cms返回到列表中.将datagrid的数据源设置为列表.正确显示第一行但我需要显示两行.希望有人能提供帮助.谢谢.

Answer 1

你可以退货List<NameAddrmark>:

public List<NameAddrmark> GetNameRespCommentData(string respid)
{
    List<NameAddrmark> cmsList = new List<NameAddrmark>();

    SqlConnection connection = new SqlConnection("");

    string sql = "SELECT top 2 * FROM dbo.RESPONDENT_COMMENT WHERE respid = " + GeneralData.AddSqlQuotes(respid) + " and USRNME = " + GeneralData.AddSqlQuotes(UserInfo.UserName) + " order by COMMDATE ASC";
    SqlCommand command = new SqlCommand(sql, connection);

    try
    {
        connection.Open();
        SqlDataReader reader = command.ExecuteReader(CommandBehavior.SingleResult);

        while (reader.Read())
        {
            NameAddrmark cms = new NameAddrmark();
            cms.Id = respid;
            cms.Date8 = reader["COMMDATE"].ToString();
            cms.Usrnme = reader["USRNME"].ToString();
            cms.Marktext = reader["COMMTEXT"].ToString();
            cmsList.Add(cms);
        }
    } catch (SqlException ex)
    {
        throw ex;
    } finally
    {
        connection.Close();
    }
    return cmsList;
}

但是你应该使用参数而不是字符串连接来防止sql注入.