博客开发手记1 – 不能发布URL长度超过280字符微博的解决方案(C#实现)

开发微博PPC客户端时发现，不能发布URL长度超过280字符的微博(网页端也有此问题)，例如发布一个淘宝商品图片：URL http://www.taobao.com/view_image.php?pic=Wx0GGlFDXA1VUwMFWx0SCwkNGRFcVxxQW1UcCxMFRBkDCFdVV1cRRhpTRDhHQghddWtdVEAxKgtSA0MHZ2sDBUBfRlJFBgYV&title=zeLDs8zYvNvP5LD8ILH2usBCSU5IQU%2FV%2Fca3IMLD0NDP5C%2B1x7v6z%2BQvzdDUy8%2FkL8CtuMvP5DI0tOc%3D&version=2&c=OTgzMDkyZWY2Njk3MjI4ZmI2ZGUzMjdlYTkyODEyOTI%3D&itemId=85a8fa3ca3d4933e7e6d57714c28105a&dbId=db1&fv=9。

 

直接将此URL输入到信息框，将提示信息超出长度，如下图：

                   WeGo(微博PPC客户端)

 

                               新浪微博网页端

 

 

 

 

使用WeGo的URL短地址编辑器即可实现发布此微博，具体操作如下：

1.进入短地址编辑界面

2.输入要缩短的URL，点击"确定"

3.生成短地址，发布微博

 

 

 

 

 

具体解决方案如下：

使用ShortText.com  或 TinyURL.com等短地址生成网站的API生成短地址，然后使用短地址发布微博。

本文以ShortText.com API为例，使用C#实现，具体实现如下：

 

    public class ShortTextURL

    {

        private const string APIURL = "http://shortText.com/api.aspx";

 

       

        public string GetShortenedText(string inputText)

        {

            string data = "shorttext=" + HttpUtility.UrlEncode(inputText);

            const int trimLength = 5;

            string shortenURL = ExecutePostCommand(APIURL, data);

            if (!string.IsNullOrEmpty(shortenURL))

            {

                string newText =

                    inputText.Substring(0, inputText.LastIndexOf(" ", 140 - (shortenURL.Length + trimLength))) + " " +

                    shortenURL;

                return newText;

            }

            return inputText;

        }

 

        private static string ExecutePostCommand(string url, string data)

        {

            var request = CreateHttpRequest(new Uri(url));

           

            request.ContentType = "application/x-www-form-urlencoded";

            request.Method = "POST";

            request.Timeout = 20000;

           

            byte[] bytes = Encoding.UTF8.GetBytes(data);

 

            request.ContentLength = bytes.Length;

            try

            {

                using (var requestStream = request.GetRequestStream())

                {

                    requestStream.Write(bytes, 0, bytes.Length);

                    requestStream.Flush();

                }

            }

            catch (Exception)

            {

 

            }

 

            try

            {

                using (var response = (HttpWebResponse)request.GetResponse())

                {

                    using (var reader = new StreamReader(response.GetResponseStream()))

                    {

                        return reader.ReadToEnd();

                    }

                }

            }

            catch (WebException ex)

            {

                System.Diagnostics.Debug.WriteLine(ex.Message);

            }

            return null;

        }           

    }