天气预报

最新推荐文章于 2024-07-15 09:55:08 发布

原创最新推荐文章于 2024-07-15 09:55:08 发布 · 900 阅读

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#string #exception #class #url #null #date

本文介绍了一个使用C#编写的简单天气预报抓取程序。该程序通过网络爬虫技术从特定网站获取并解析天气信息，包括城市、日期、天气状况、温度、风力及光照情况等。代码详细展示了如何实现数据的抽取和格式化。

/// <summary>
 /// 天气预报
 /// </summary>
 public class weather
 {
 #region 公共属性
 /// <summary>
 /// 城市
 /// </summary>
 public string City;
 /// <summary>
 /// 日期
 /// </summary>
 public string Date;
 /// <summary>
 /// 天气
 /// </summary>
 public string WeatherInfo;
 /// <summary>
 /// 温度
 /// </summary>
 public string Temperature;
 /// <summary>
 /// 风
 /// </summary>
 public string Wind;
 /// <summary>
 /// 光
 /// </summary>
 public string Light;

#endregion 公共属性

#region ==方法==
 /// <summary>
 /// 解析指定城市的天气
 /// </summary>
 /// <param name="cityWeatherPageText"></param>
 /// <returns></returns>
 public void PasreCityWeather(string cityWeatherPageText)
 {
 //解析时间
 this.ParseDate(cityWeatherPageText);
 //解析天气
 this.ParseWeather(cityWeatherPageText);
 //解析温度
 this.ParseTemperature(cityWeatherPageText);
 //解析风，光
 this.ParseWindAndLight(cityWeatherPageText);
 }
 public override string ToString()
 {
 //string LN = "/r/n";
 //string result = "南昌日期：" + this.Date + LN;
 //result += "天气：" + this.WeatherInfo + LN;
 //result += "温度：" + this.Temperature + LN;
 //result += "风：" + this.Wind + LN;
 //result += "" + this.Light + LN;
 if (this.Temperature == "") this.Temperature = "4℃";

string LN = "/r/n";
 string result = "南昌 "; //+ this.Date + LN;
 result += this.WeatherInfo + LN;
 result += this.Temperature + LN;
 return result;
 }
 #region 私有方法
 /// <summary>
 /// 解析时间
 /// </summary>
 /// <param name="cityWeatherPageText"></param>
 private void ParseDate(string cityWeatherPageText)
 {
 this.Date = this.GetStringBetween(cityWeatherPageText, "", "").Trim();
 }
 /// <summary>
 /// 解析天气
 /// </summary>
 /// <param name="cityWeatherPageText"></param>
 private void ParseWeather(string cityWeatherPageText)
 {
 this.WeatherInfo = this.GetStringBetween(cityWeatherPageText, "class=/"weather/">", "</td>").Trim();
 }
 /// <summary>
 /// 解析温度
 /// </summary>
 /// <param name="cityWeatherPageText"></param>
 private void ParseTemperature(string cityWeatherPageText)
 {
 this.Temperature = this.GetStringBetween(cityWeatherPageText, "class=/"weatheren/">", "</td>").Trim();
 }
 /// <summary>
 /// 解析风，光
 /// </summary>
 /// <param name="cityWeatherPageText"></param>
 private void ParseWindAndLight(string cityWeatherPageText)
 {
 string windAndLight = this.GetStringBetween(cityWeatherPageText, "<td width=/"153/" valign=/"top/">", "</td>");
 this.Wind = this.GetStringBetween(windAndLight, "", " ").Trim();
 this.Light = this.GetStringBetween(windAndLight, " ", "").Trim();
 }
 /// <summary>
 /// HTML解释
 /// </summary>
 /// <param name="sourceString">源字符串</param>
 /// <param name="startString">需要解释的字符串开头</param>
 /// <param name="endString">需要解释的字符串结尾</param>
 /// <returns></returns>
 private string GetStringBetween(string sourceString, string startString, string endString)
 {
 int startPos = sourceString.IndexOf(startString) + startString.Length;
 int endPos = sourceString.IndexOf(endString, startPos);
 string result = sourceString.Substring(startPos, endPos - startPos);
 return result;
 }
 #endregion 私有方法
 #endregion

}

/// <summary>
 /// 获取远程文件内容
 /// </summary>
 public class Spider
 {
 ArrayList alWeather = null;
 /// <summary>
 ///
 /// </summary>
 private string weatherSiteURL = @"http://weather.tq121.com.cn/";
 /// <summary>
 /// 城市查找
 /// </summary>
 private string cityWeatherURL = @"http://weather.tq121.com.cn/mapanel/index1.php?city=";
 #region 构造函数
 public Spider()
 {
 alWeather = new ArrayList();
 if (System.Configuration.ConfigurationSettings.AppSettings["weatherSiteUrl"] != null)
 {
 this.weatherSiteURL = System.Configuration.ConfigurationSettings.AppSettings["weatherSiteUrl"];
 }
 if (System.Configuration.ConfigurationSettings.AppSettings["cityWeatherURL"] != null)
 {
 this.cityWeatherURL = System.Configuration.ConfigurationSettings.AppSettings["cityWeatherURL"];
 }

}
 #endregion 构造函数
 /// <summary>
 /// 取得指定城市的天气
 /// </summary>
 /// <param name="city"></param>
 /// <returns></returns>
 public weather GetWeather(string city)
 {
 string encodedCity = System.Web.HttpUtility.UrlEncode(city, System.Text.Encoding.Default);
 string url = this.cityWeatherURL + encodedCity;
 Console.WriteLine(url);
 string cityWeatherPageText = this.GetPageText(url);
 weather cityWeather = new weather();
 cityWeather.PasreCityWeather(cityWeatherPageText);
 return cityWeather;
 }
 /// <summary>
 /// 取得页面文本
 /// </summary>
 /// <returns></returns>
 private string GetPageText(string url)
 {
 WebClient wc = new WebClient();
 try
 {
 byte[] dataArray = wc.DownloadData(url);
 string weatherPageText = System.Text.Encoding.Default.GetString(dataArray);
 return weatherPageText;
 }
 catch (Exception ex)
 {
 throw new Exception("打开天气页面失败/r/n" + ex.Message);
 }
 }
 }