找http://开头含blog的链接作为目标链接

爬虫/Program.cs

@@ -0,0 +1,58 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using System.IO;
+using System.Net;
+using System.Text.RegularExpressions;
+
+
+namespace ConsoleApplication1
+{
+    class Program
+    {
+        static void Main(string[] args)
+        {
+            System.Net.WebClient client = new WebClient();
+            Stream strm = client.OpenRead("http://www.baidu.com/s?word=hdu%201202&pn=0");
+            StreamReader sr = new StreamReader(strm);
+            string line;
+            StreamWriter sw = new StreamWriter("D:\\1.txt");
+            int num = 1;
+
+            while ((line = sr.ReadLine()) != null)
+            {
+                for (int i = 0; i < line.Length - 7; i++)//找line中的http开头的链接
+                {
+                    if (line[i] == 'h')
+                    {
+                        if (line[i + 1] == 't' && line[i + 2] == 't' && line[i + 3] == 'p' && line[i + 4] == ':')
+                        {
+                            int last = i + 7;
+                            while (last < line.Length && line[last++] != '"') ;
+                            last--;
+                            if (line[last] == '"')
+                            {
+                                string temp = line.Substring(i, last - i);
+                                int find_blog = temp.IndexOf("blog");
+                                int find_baidu = temp.IndexOf("baidu");
+                                if (find_blog != -1 && find_baidu==-1)
+                                {
+                                    temp = temp.Replace("\\", "");
+                                    Console.WriteLine("["+num.ToString()+"]"+temp);
+                                    sw.WriteLine("[" + num.ToString() + "]" + temp);
+                                    client.DownloadFile(temp, "D:\\download"+num.ToString() + ".html");
+                                    num++;
+                                }
+                            }
+                        }
+                    }
+                }
+               // sw.WriteLine("\n--------------------------------------------------------------\n");
+            }
+            sw.Close();
+            strm.Close();
+        }
+    }
+}