Public methods of the Winform-webclient class

From the definition of MSDN: The WebClient class provides public methods for sending data to and receiving data from local, intranet, Internet resources identified to any URI.

We will recognize the usage of WebClient from a relatively long example. Program more than 100 lines, and No comments. But the follow-up will be added.

This example is done by invoking the APIs provided by Ip138 and Taobao to obtain an extranet IP and IP attribution method.

The first is the three functions used:

1 ///get the extranet IP address as the school is on the local area network. So it's more trouble .2 Private Static stringgetipaddress ()3 {4     stringTempip ="";5     Try6         {7WebRequest WR = WebRequest.Create ("http://www.ip138.com/ip2city.asp");8Stream s =WR. GetResponse (). GetResponseStream ();9StreamReader sr =NewStreamReader (S, encoding.default);Ten                 stringall = Sr. ReadToEnd ();//reading data from a Web site One  A                 intStart = all. IndexOf ("[") +1; -                 intEnd = All. IndexOf ("]", start); -Tempip = All. Substring (Start, End-start); the Sr. Close (); - s.close (); -     } -     Catch +     { -     } +     returnTempip; A}

1 ///obtaining IP attribution information based on the acquired extranet IP2  Public voidThreadProc (stringIP)3         {4             if(!isvaildipaddress (IP))5             {6MessageBox.Show ("illegal","Error", MessageBoxButtons.OK,7 messageboxicon.error);8             }9WebClient client =NewWebClient ();Ten             stringURI =@"http://ip.taobao.com/service/getIpInfo.php?ip="+IP; One             stringJsondata =Client. Downloadstring (URI);
The following statement requires a reference to Json.dll AIpcheckresult result = jsonconvert.deserializeobject<ipcheckresult> - (jsondata); -             if(Result.code! =0) the             { -MessageBox.Show ("Not Found"); -             } -TextBox1.Text =result.data.Region; +TextBox2.Text =result.data.City; -TextBox3.Text = Result.data.Country +Result.data.ISP; +Textbox4.text = Result.data.Area +"Area"; A}

/// verifying IP with regular expressions Private BOOL Isvaildipaddress (string  IP)        {            string@ "^ (?:(? : 25[0-5]|2[0-4]\d| ((1\d{2}) | ([1-9]?\d))) \.) {3} (?: 25[0-5]|2[0-4]\d| ((1\d{2}) | ([1-9]?\d)))) $";             return regex.ismatch (IP, pattern);        }

Form_Load Event Invocation
1  privatevoid Form1_Load (object  sender, EventArgs e)2         { 3             string IP = getipaddress (); 4             New Thread (() = ThreadProc (IP));
Always feel that the LAMDA expression is a good way for a thread to invoke a function that has parameters ....  5            thread. Start (); 6         }

Finally, two custom classes are used:

1 namespaceIPAddress2 {3     classIpaddressdata4     {5          Public stringCountry;//get the city where the IP resides6          Public stringarea;//get IP in your region7          Public stringregion;//get the province of your IP8          Public stringCity;//Get IP City9          Public stringISP;//Get IP-owned carriersTen          PublicIpaddressdata () One         { } A     } -}

1 namespace IPAddress 2 {3     class Ipcheckresult 4     {5public         int  code; 6          Public ipaddressdata data; 7     }8 }

Program results:

As for the program running up encountered from not creating the control of the thread access control, crossing Baidu a bit on the line. There are several workarounds. ('? ') )

Public methods of the Winform-webclient class