/* 2012년 8월 현재 구글 날씨 API 서비스가 지원되지 않기 때문에 이 프로그램은 정상적으로 동작하지 않습니다 */

.NET 의 LINQ 를 사용해보다가 심심해서 예제를 제작했습니다.
이전에 JAVA로 만들었던 기상정보 프로그램을 UI도 갖추고 해서 조금(?) 더 이쁘게 C#으로 만들었습니다.

(2012년 6월 25일 최종업데이트)

using System;

using System.Collections.Generic;

using System.ComponentModel;

using System.Data;

using System.Drawing;

using System.Linq;

using System.Text;

using System.Windows.Forms;

using System.Xml.Linq;

namespace LINQ

{

    public partial class LIQMain : Form

    {

        public class pair<T, U>

        {

            public pair() { }

            public pair(T First, U Second) { first = First; second = Second; }

            public T first { get; set; }

            public U second { get; set; }

        }

        protected List<pair<string, string>> m_cityList = new List<pair<string, string>>();

        public LIQMain()

        {

            InitializeComponent();

            LoadCities();

            getWeather(m_cityList[dropCities.SelectedIndex].first);

        }

        protected void LoadCities()

        {

            m_cityList.Add(new pair<string, string>("seoul", "서울"));

            m_cityList.Add(new pair<string, string>("incheon", "인천"));

            m_cityList.Add(new pair<string, string>("suwon", "수원"));

            m_cityList.Add(new pair<string, string>("osan", "오산"));

            m_cityList.Add(new pair<string, string>("hwaseong-si", "화성"));

            m_cityList.Add(new pair<string, string>("pyeongtaek", "평택"));

            m_cityList.Add(new pair<string, string>("yongin", "용인"));

            m_cityList.Add(new pair<string, string>("cheonan", "천안"));

            m_cityList.Add(new pair<string, string>("wonju", "원주"));

            m_cityList.Add(new pair<string, string>("chungju", "청주"));

            m_cityList.Add(new pair<string, string>("mokpo", "목포"));

            m_cityList.Add(new pair<string, string>("jeonju", "전주"));

            m_cityList.Add(new pair<string, string>("daegu", "대구"));

            m_cityList.Add(new pair<string, string>("gwangju", "광주"));

            m_cityList.Add(new pair<string, string>("pohang", "포항"));

            m_cityList.Add(new pair<string, string>("busan", "부산"));

            m_cityList.Add(new pair<string, string>("jeju", "제주"));

            foreach (pair<string, string> item in m_cityList)

            {

                dropCities.Items.Add(item.second);

            }

            dropCities.SelectedIndex = 0;

        }

        protected void getWeather(string strCity)

        {

            XDocument xmlDoc = XDocument.Load(String.Format("http://www.google.com/ig/api?weather={0}&ie=utf-8&oe=utf-8&hl=ko",strCity));

            var forcast_date = from weather in xmlDoc.Descendants("forecast_information")

                               select new

                               {

                                   date = weather.Element("forecast_date").Attribute("data").Value

                               };

            var weather_cast = from weather in xmlDoc.Descendants("current_conditions")

                            select new 

                            {

                                cur_weather = weather.Element("condition").Attribute("data").Value,

                                cur_temp_c = weather.Element("temp_c").Attribute("data").Value,

                                cur_humidity = weather.Element("humidity").Attribute("data").Value,

                                cur_wind = weather.Element("wind_condition").Attribute("data").Value,

                                cur_icon = weather.Element("icon").Attribute("data").Value

                            };

            var forecast = from foreweather in xmlDoc.Descendants("forecast_conditions")

                           select new

                           {

                               fore_day = foreweather.Element("day_of_week").Attribute("data").Value,

                               fore_low_temp = foreweather.Element("low").Attribute("data").Value,

                               fore_high_temp = foreweather.Element("high").Attribute("data").Value,

                               fore_weather = foreweather.Element("condition").Attribute("data").Value,

                               fore_icon = foreweather.Element("icon").Attribute("data").Value

                           };

            // 일기예보 일자

            if (forcast_date.Count() > 0)

            {

                string castDate = forcast_date.ElementAt(0).date;

                lblCastDate.Text = String.Format("일기예보 일자 : {0}", castDate.Replace('-', '.'));

            }

            else

                lblCastDate.Text = "-";

            // 현재 날씨

            if (weather_cast.Count() > 0)

            {

                weatherBox.Text = String.Format("{0}의 현재 날씨", m_cityList[dropCities.SelectedIndex].second);

                lblCWeather.Text = String.Format("{0}", weather_cast.ElementAt(0).cur_weather);

                lblCTemp.Text = String.Format("기온 : {0} ℃", weather_cast.ElementAt(0).cur_temp_c);

                lblCHumid.Text = String.Format("습도 : {0}",weather_cast.ElementAt(0).cur_humidity.Substring(weather_cast.ElementAt(0).cur_humidity.LastIndexOf(":")+1).Trim());

                lblCWind.Text = String.Format("풍향 : {0}",weather_cast.ElementAt(0).cur_wind.Substring(weather_cast.ElementAt(0).cur_wind.LastIndexOf(":")+1).Trim());

                try

                {

                    imgIcon.Load(String.Format("http://www.google.co.kr{0}",weather_cast.ElementAt(0).cur_icon));

                }

                catch (System.Exception)

                {

                }

            }

            // 내일 날씨

            if (forecast.Count() > 1)

            {

                foreBox.Text = String.Format("내일({0}) 날씨",forecast.ElementAt(1).fore_day);

                lblFWeather.Text = String.Format("{0}", forecast.ElementAt(1).fore_weather);

                lblFTempLow.Text = String.Format("최저 기온 : {0} ℃", forecast.ElementAt(1).fore_low_temp);

                lblFTempHigh.Text = String.Format("최고 기온 : {0} ℃", forecast.ElementAt(1).fore_high_temp);

                try

                {

                    imgFIcon.Load(String.Format("http://www.google.co.kr{0}", forecast.ElementAt(1).fore_icon));

                }

                catch (System.Exception)

                {

                }

            }

        }

        private void btnRefresh_Click(object sender, EventArgs e)

        {

            if (dropCities.SelectedIndex < 0)

                return;

            try

            {

                getWeather(m_cityList[dropCities.SelectedIndex].first);

            }

            catch (System.Exception ex)

            {

                MessageBox.Show(ex.Message, this.Text, MessageBoxButtons.OK, MessageBoxIcon.Information);

                return;

            }

        }

    }

}

Programatically Set or Change DataRow's RowState

  The .NET Framework 2.0 adds a new feature: SetAdded, SetModified. You use this feature to set DataRow's RowState value programatically. This is applicable only when the current DataRow's RowState is Unchanged.

Simply use the following steps:

Make the necessary changes to the DataRow.

  Call AcceptChanges() for the DataRow. When invoking AcceptChanges, any DataRow object still in edit mode successfully ends its edit. Each DataRow's RowState property also changes; the Added and Modified rows become Unchanged,
and the Deleted rows are removed:

dsCopySess.Tables["DataTableName"].Rows[0].AcceptChanges();

Set the RowState as desired:

dsCopySess.Tables["DataTableName"].Rows[0].SetAdded();

요약하면 RowState 가 Unchanged 상태에서

아래처럼,
dsCopySess.Tables["DataTableName"].Rows[0].SetAdded();

데이터셋.테이블[인덱스].행[행번호].원하는 상태(SetAdded, SetModified....) 을 호출해주면 된다는 겁니다~


출처 : http://www.devx.com/tips/Tip/39112

" 이 행은 이미 다른 테이블에 속해 있습니다 "

" This row already belongs to another table. "


DataRow 를 DataSet 에 잘못된 방법(기존 행을 바로 추가하는 방식 등)으로 추가하려는 경우 가끔 이런 문제가 생기는데
아래처럼 ItemArray 를 이용하면 해결된다.


DataRow row = table.rows[0];
dataset.Tables[0].Rows.Add(row.ItemArray);

KeyValuePair<TKey, TValue> Structure