YsZUDLyh

1using System;
2using System.IO;
3
4using System.Data;
5using System.Net;
6using System.Windows.Forms;
7
8using System.Xml;
9using System.Data.SQLite;
10
11namespace LAB_7_8
12{
13    public partial class Form1 : Form
14    {
15        News newsForm = new News();
16
17        const string link = "https://news.yandex.ru/health.rss";
18
19        public Form1()
20        {
21            InitializeComponent();
22        }
23
24        private void GetDataButton_Click(object sender, EventArgs e) // получение новостей с сайта в формате XML
25        {
26            try
27            {
28                string strNews;
29                HttpWebRequest request = (HttpWebRequest)WebRequest.Create(link);
30                HttpWebResponse response = (HttpWebResponse)request.GetResponse();
31                Stream stream = response.GetResponseStream();
32                StreamReader reader = new StreamReader(stream);
33                strNews = reader.ReadToEnd();
34
35                richTextBoxShowData.Text = strNews;
36
37                XmlDocument xmlNews = new XmlDocument();
38                xmlNews.LoadXml(strNews);
39                newsForm.ClearNews();
40
41                XmlNodeList childNodeList = xmlNews.DocumentElement.SelectSingleNode("channel").SelectNodes("item");
42
43                foreach (XmlNode xmlNode in childNodeList)
44                {
45                    newsForm.addNewsToList(
46                        xmlNode.SelectSingleNode("title").InnerText,
47                        xmlNode.SelectSingleNode("link").InnerText,
48                        xmlNode.SelectSingleNode("description").InnerText,
49                        xmlNode.SelectSingleNode("pubDate").InnerText
50                    );
51                }
52
53                showNews.Visible = true;
54            } catch (Exception err)
55            {
56                richTextBoxShowData.Text = $"Ошибка получения новостей! {err.Message}";
57            }
58        }
59
60        private void WriteDataToDB_Click(object sender, EventArgs e) // запись полученных с сайта новостей в базу данных
61        {
62            try
63            {
64                if (newsForm.newsList.Count != 0)
65                {
66                    SQLiteConnection db;
67                    db = new SQLiteConnection("Data Source = dataBase.db;");
68                    db.Open();
69
70                    new SQLiteCommand("PRAGMA synchronous = 1; CREATE TABLE IF NOT EXISTS News(Id INTEGER PRIMARY KEY AUTOINCREMENT, Title, Link, Description, PubDate); ", db).ExecuteNonQuery(); ;
71
72                    new SQLiteCommand("DELETE FROM News", db).ExecuteNonQuery();
73
74                    foreach (News.NewsData news in newsForm.newsList)
75                    {
76                        new SQLiteCommand($"INSERT INTO News(Title,Link,Description,PubDate) VALUES('{news.title}','{news.link}','{news.desc}', '{news.time}')", db).ExecuteNonQuery();
77                    }
78
79                    newsForm.ClearNews();
80                    richTextBoxShowData.Text = "Новости записаны в базу данных.";
81                }
82                else
83                {
84                    richTextBoxShowData.Text = "Ошибка! Список новостей пуст!";
85                }
86            }
87            catch (Exception err)
88            {
89                richTextBoxShowData.Text = $"Ошибка записи! {err.Message}";
90            }
91        }
92
93        private void ReadDataFromDB_Click(object sender, EventArgs e) // выгрузка новостей из дб
94        {
95            try
96            {
97                SQLiteConnection db;
98                db = new SQLiteConnection("Data Source = dataBase.db;");
99                db.Open();
100
101                SQLiteCommand command = new SQLiteCommand("PRAGMA synchronous = 1; CREATE TABLE IF NOT EXISTS News(Id INTEGER PRIMARY KEY AUTOINCREMENT, Title, Link, Description, PubDate); ", db);
102                command.ExecuteNonQuery();
103
104                SQLiteDataReader reader = new SQLiteCommand("SELECT * FROM News", db).ExecuteReader();
105
106                newsForm.ClearNews();
107
108                foreach (IDataRecord item in reader)
109                {
110                    newsForm.addNewsToList(
111                        item["Title"].ToString(),
112                        item["Link"].ToString(),
113                        item["Description"].ToString(),
114                        item["PubDate"].ToString()
115                    );
116                }
117
118                richTextBoxShowData.Text = "Новости считаны из базы данных.";
119                showNews.Visible = true;
120
121                db.Close();
122                db.Dispose();
123            } catch (Exception err)
124            {
125                richTextBoxShowData.Text = $"Ошибка чтения! {err.Message}";
126            }
127        }
128
129        private void ShowNews_Click(object sender, EventArgs e)
130        {
131            newsForm.Show(); // открытие окна с новостями
132        }
133    }
134}
135