用于查询 SQL Server 并返回结果的 Web API 未按预期工作

Question

我正在尝试从 Web API 连接到 SQL Server 并将结果集返回为 JSON。但是我在这里显示的代码没有按预期工作。我正在尝试将整个查询响应作为 JSON 返回：

[HttpGet]
public HttpResponseMessage Getdetails(string ROOM)
{
    string commandText = "SELECT * from [TDB].[dbo].[results_vw] where ROOM = @ROOM_Data";

    string connStr = ConfigurationManager.ConnectionStrings["TDBConnection"].ConnectionString;

    var jsonResult = new StringBuilder();

    using (SqlConnection connection = new SqlConnection(connStr))
    {
        SqlCommand command = new SqlCommand(commandText, connection);
        command.Parameters.Add("@ROOM_Data", SqlDbType.VarChar);
        command.Parameters["@ROOM_Data"].Value = ROOM;

        connection.Open();

        var reader = command.ExecuteReader();

        if (!reader.HasRows)
        {
            jsonResult.Append("[]");
        }
        else
        {
            while (reader.Read())
            {
                jsonResult.Append(reader.GetValue(0).ToString());
            }
        }

        var response = new HttpResponseMessage(System.Net.HttpStatusCode.OK);
        response.Content = new StringContent(jsonResult.ToString());

        connection.Close();

        return response;
    }
}

此代码返回此结果：

333838362692368203368203368203362692368203359544362692368203362692368203362692368203368203

我期望 JSON 为

 {"data":
  [
  {"R_ID":"368203","ROOM":"K2"}, 
  {"R_ID":"368203","ROOM":"K2"}
  ]}

现在我创建了一个名为 DatabaseResult 的模型类来存储响应，但我不确定如何将结果存储到控制器中的模型类中

public class DatabaseResult
{
      public int r_id { get; set; }
      public string room { get; set; }
}

Answer 1

当前结果是因为您只返回每行第一列的值并将其添加到字符串生成器。

创建模型的新实例并使用读取器中每行的值填充它。

[HttpGet]
public IHttpActionResult Getdetails(string ROOM) {
    string commandText = "SELECT * from [TDB].[dbo].[results_vw] where ROOM = @ROOM_Data";
    string connStr = ConfigurationManager.ConnectionStrings["TDBConnection"].ConnectionString;
    var jsonResult = new StringBuilder();
    using (SqlConnection connection = new SqlConnection(connStr)) {
        using (SqlCommand command = new SqlCommand(commandText, connection)) {
            command.Parameters.Add("@ROOM_Data", SqlDbType.VarChar);
            command.Parameters["@ROOM_Data"].Value = ROOM;
            connection.Open();
            List<DatabaseResult> records = new List<DatabaseResult>();
            using (var reader = command.ExecuteReader()) {
                while (reader.Read()) {
                    var row = new DatabaseResult {
                        r_id = (int)reader["r_id"],
                        room = (string)reader["room"],
                        //...other properties.
                    };
                    records.Add(row);
                }
                return Ok(records);
            }
        }
    }
}

上面使用列名作为索引器从读取器获取值。