ncsi이용해서 네트워크 상태 구현함

Add network status

Catswords.DataType.Client/Helper/FileExtensionDB.cs

@@ -1,7 +1,11 @@
 using Catswords.DataType.Client.Model;
 using System;
 using System.Collections.Generic;
+using System.Diagnostics;
+using System.Linq;
 using System.Net;
+using System.Net.Http;
+using System.Net.NetworkInformation;
 using System.Text;
 using System.Windows.Forms;
 using System.Xml;
@@ -17,6 +21,7 @@ namespace Catswords.DataType.Client.Helper
             Indicators = new List<Indicator>();
         }
 
+
         public void Fetch(string q)
         {
             try
@@ -24,6 +29,7 @@ namespace Catswords.DataType.Client.Helper
                 // 원격 주소에서 XML 다운로드
                 string url = Config.SEARCH_URL + q;
                 WebClient client = new WebClient();
+
                 client.Headers.Add("User-Agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/58.0.3029.110 Safari/537.3");
                 client.Encoding = Encoding.UTF8;
                 string xmlString = client.DownloadString(url);

Catswords.DataType.Client/UserControl1.cs

@@ -1,4 +1,4 @@
-using Catswords.DataType.Client.Helper;
+using Catswords.DataType.Client.Helper;
 using Catswords.DataType.Client.Model;
 using System;
 using System.ComponentModel.Design;
@@ -6,6 +6,7 @@ using System.Diagnostics;
 using System.Drawing;
 using System.IO;
 using System.Linq;
+using System.Net;
 using System.Windows.Forms;
 
 namespace Catswords.DataType.Client
@@ -81,7 +82,42 @@ namespace Catswords.DataType.Client
             ExtractLink();
         }
 
+        bool IsInternetConnected()
+        {
+            const string NCSI_TEST_URL = "http://www.msftncsi.com/ncsi.txt";
+            const string NCSI_DNS = "dns.msftncsi.com";
+            const string NCSI_DNS_IP_ADDRESS = "131.107.255.255";
+
+
+            try
+            {
+                // Check NCSI test link
+                var webClient = new WebClient();
+                string result = webClient.DownloadString(NCSI_TEST_URL);
+                if (result != "Microsoft NCSI")
+                {
+                    return false;
+                }
+
+                // Check NCSI DNS IP
+                var dnsHost = Dns.GetHostEntry(NCSI_DNS);
+                if (dnsHost.AddressList.Count() < 0 || dnsHost.AddressList[0].ToString() != NCSI_DNS_IP_ADDRESS)
+                {
+                    return false;
+                }
+            }
+            catch (Exception ex)
+            {
+                Debug.WriteLine(ex);
+                return false;
+            }
+
+            return true;
+        }
+
         private void FetchFromFileExtensionDB()
+        {
+            if (IsInternetConnected())
             {
                 var search = new FileExtensionDB();
                 search.Fetch(fileExtension);
@@ -89,6 +125,12 @@ namespace Catswords.DataType.Client
                 {
                     listView1.Items.Add(new ListViewItem(new string[] { ind.CreatedAt.ToString(), ind.Content }, 0));
                 }
+            } else
+            {
+                MessageBox.Show("인터넷에 연결되어 있지 않습니다.", "오류", MessageBoxButtons.OK, MessageBoxIcon.Error);
+                return;
+            }
+
         }
 
         private void FetchFromTimeline()