From a2fffe2dc140e101487983b5f3080c77eb72ef9e Mon Sep 17 00:00:00 2001
From: komaruchan <sandy_0308@hotmail.com>
Date: Thu, 4 Jun 2015 00:07:48 +0800
Subject: [PATCH] detect whether online before checking update.

---
 mp4box/MainForm.cs | 17 ++++++++++++-----
 mp4box/Util.cs     | 15 +++++++++++++++
 2 files changed, 27 insertions(+), 5 deletions(-)

diff --git a/mp4box/MainForm.cs b/mp4box/MainForm.cs
index fa557cf..c61b69f 100644
--- a/mp4box/MainForm.cs
+++ b/mp4box/MainForm.cs
@@ -883,7 +883,7 @@ namespace mp4box
                 else
                     languageComboBox.SelectedIndex = int.Parse(ConfigurationManager.AppSettings["LanguageIndex"]);
 
-                if (CheckUpdateCheckBox.Checked)
+                if (CheckUpdateCheckBox.Checked && Util.IsConnectInternet())
                 {
                     DateTime d;
                     bool f;
@@ -3765,10 +3765,17 @@ namespace mp4box
 
         private void CheckUpdateButton_Click(object sender, EventArgs e)
         {
-            WebRequest request = WebRequest.Create("http://mtbftest.sinaapp.com/version.php");
-            request.Credentials = CredentialCache.DefaultCredentials;
-            // Get the response.
-            request.BeginGetResponse(new AsyncCallback(OnResponse), request);
+            if (Util.IsConnectInternet())
+            {
+                WebRequest request = WebRequest.Create("http://mtbftest.sinaapp.com/version.php");
+                request.Credentials = CredentialCache.DefaultCredentials;
+                // Get the response.
+                request.BeginGetResponse(new AsyncCallback(OnResponse), request);
+            }
+            else
+            {
+                ShowErrorMessage("这台电脑似乎没有联网呢~");
+            }
         }
 
         protected void OnResponse(IAsyncResult ar)
diff --git a/mp4box/Util.cs b/mp4box/Util.cs
index 80a596c..6d5ced3 100644
--- a/mp4box/Util.cs
+++ b/mp4box/Util.cs
@@ -26,6 +26,8 @@ using System.Diagnostics;
 using System.Windows.Forms;
 using System.IO;
 using System.Threading;
+using System.Net.NetworkInformation;
+using System.Runtime.InteropServices;
 
 namespace mp4box
 {
@@ -216,5 +218,18 @@ namespace mp4box
             return true;
         }
 
+
+
+        [DllImport("wininet.dll")]
+        private extern static bool InternetGetConnectedState(int Description, int ReservedValue);
+        /// <summary>
+        /// 用于检查网络是否可以连接互联网,true表示连接成功,false表示连接失败 
+        /// </summary>
+        /// <returns></returns>
+        public static bool IsConnectInternet()
+        {
+            int Description = 0;
+            return InternetGetConnectedState(Description, 0);
+        }
     }
 }
-- 
2.11.4.GIT