Line 1:<asp:Label  runat="server"
Line 2: ID="lb1"   ....
Line 3:.../> 

public static String Replace(String source,String oldStr,String newStr)
       {
           int count = Regex.Matches(source, oldStr).Count;
           for (int i = 0; i < count; i++)
           {
               source = source.Replace(oldStr, newStr);
           }
           return source;
       }

       /// <summary>
       /// 压缩指定路径的文件空白字符串和换行符
       /// 压缩说明
       /// 1）采取File.ReadAllLines读取所有行每一行做处理工作
       /// 2）服务器控件最好写在一行内，只做了尾部标签与runat="server"跨行的处理，开始标签跨行为处理
       /// 3）文件不能有单行注释"//"
       /// 4）替换掉了换行符和空格
       /// </summary>
       /// <param name="filePath">文件路径</param>
       public static void CompressLineByLine(String filePath)
       {
           if (!File.Exists(filePath))
           {
               Console.WriteLine("文件不存在，检查路径{0}", filePath);
               return;
           }
           var start = DateTime.Now;
           Console.WriteLine("正在压缩文件:{0}\r\n开始于{1}...",
filePath,start.ToString());
           var lines = File.ReadAllLines(filePath,
Encoding.GetEncoding("GB2312"));
           for (int i = 0; i < lines.Length; i++)
           {
               var item = lines[i].Trim();
               if (item.IndexOf("runat=\"server\"") > -1)
                   item += " ";
               item = item.Replace("\r\n", "");
               item = Replace(item, "  ", " ");
               lines[i] = item;
           }
           File.WriteAllText(filePath, string.Join("", lines),
Encoding.GetEncoding("GB2312"));
           var end = DateTime.Now;
           Console.WriteLine("结束于{0}...", end.ToString());
           Console.WriteLine("====耗时====\r\n{0}\r\n", end - start);
       }

       /// <summary>
       /// 压缩指定路径的文件空白字符串和换行符
       /// 压缩说明
       /// 1）一次性读取出所有的文本替换掉换行符和空白
       /// 2）无须处理服务器控件换行的问题
       /// 3）压缩不彻底，A元素的结束标签和B开始标签之间可能仍然有一个空格
       /// </summary>
       /// <param name="filePath"></param>
       public static void CompressAtOneTime(String filePath)
       {
           var start = DateTime.Now;
           Console.WriteLine("正在压缩文件:{0}\r\n开始于{1}...", filePath,
start.ToString());
           var lines = File.ReadAllText(filePath);
           File.WriteAllText(filePath, Replace(Replace(lines, "\r\n",
""),"  "," "), Encoding.GetEncoding("GB2312"));
           var end = DateTime.Now;
           Console.WriteLine("结束于{0}...", end.ToString());
           Console.WriteLine("====耗时====\r\n{0}\r\n", end - start);
       }