Question

下面的代码工作正常，但我想知道一种方法来拉出列标题吗？如果可能的话，我希望在我的while循环中。希望有人可以提供帮助。

谢谢，詹姆斯。

namespace WorldViewNet.include
{
    public class ImageHandler : IHttpHandler
    {
        public void ProcessRequest(HttpContext context)
        {
            object data = LoadAPI(context);
            string jsonData = JsonConvert.SerializeObject(data);
            context.Response.Write(jsonData);
        }

        public List<object[]> LoadAPI(HttpContext context)
        {
            List<object[]> list = new List<object[]>();
            SqlConnection sqlConnection1 = new SqlConnection(globalLibrary.NewConnectionString);
            SqlCommand cmd = new SqlCommand();
            SqlDataReader reader;
            string tablename = context.Request.QueryString["tablename"];
            string maybeID = context.Request.QueryString["ID"];

            cmd.CommandText = "SELECT * FROM " + tablename;

            if (maybeID != null)
            {
                cmd.CommandText += " WHERE " + tablename + "ID =" + maybeID;
            }

            cmd.CommandType = CommandType.Text;
            cmd.Connection = sqlConnection1;

            sqlConnection1.Open();

            reader = cmd.ExecuteReader();
            while (reader.Read())
            {
                object[] row = new object[23];
                reader.GetValues(row);
                list.Add(row);
            }
            sqlConnection1.Close();
            return list;
        }
        public bool IsReusable
        {
            get
            {
                return false;
            }
        }

    }
}

Answer 1

你应该能够做到这一点：

reader = cmd.ExecuteReader();
var columns = Enumerable.Range(0, reader.FieldCount).Select(reader.GetName).ToList();

columns现在应该是所有列名的列表。

如果您需要非Linq方式来执行此操作：

reader = cmd.ExecuteReader();
var columns = new List<string>();

for(int z=0;z<reader.FieldCount;z++)
{
   columns.Add(reader.GetName(z));
}

使用列标题在C＃中创建Json字符串

1 个答案: