应该如何更有效的优化代码,减少占用资源?
造成服务器资源100%,影响服务器运行。麻烦各位前辈 帮忙优化下代码。
如果用最简洁的方法获取快照内容。请不暂用资源。
只要能获取快照的内容即可。其他的没特别限制。
private List<string> GetCacheHtml(string strTitle)--------------------编程问答--------------------
{
WebOperation W = new WebOperation();
string strSearchHtml = W.Get(string.Format("http://www.baidu.com/s?wd={0}", System.Web.HttpUtility.UrlEncode(strTitle)));
MatchCollection CacheUrlList = RexGet("http://cache\\.baidu\\.com.*?(?=\\\")", strSearchHtml);
List<string> strHtmlList = new List<string>();
int i = 0;
foreach (Match CacheUrl in CacheUrlList)
{
//下面的2代表只获取前两条快照了,如果需要的话修改一下就可以了
i++;
if (i > 1)
{
break;
}
//获取快照数据
string strCacheHtml = W.Get(CacheUrl.Value);
//去除Baidu信息
strCacheHtml = Regex.Replace(strCacheHtml, "<.*?(?=<html)", "",
RegexOptions.Singleline | RegexOptions.IgnoreCase | RegexOptions.ExplicitCapture | RegexOptions.Singleline);
//过滤超链接
strCacheHtml = Regex.Replace(strCacheHtml, "<a.*?>", "",
RegexOptions.Singleline | RegexOptions.IgnoreCase | RegexOptions.ExplicitCapture | RegexOptions.Singleline);
strCacheHtml = strCacheHtml.Replace("</a>", "");
//过滤CSS样式
strCacheHtml = Regex.Replace(strCacheHtml, "<style.*?</style>", "",
RegexOptions.Singleline | RegexOptions.IgnoreCase | RegexOptions.ExplicitCapture | RegexOptions.Singleline);
//过滤所有HTML标记
strCacheHtml = NoHTML(strCacheHtml);
//添加到结果集
strHtmlList.Add(strCacheHtml);
}
return strHtmlList;
}
/**/
/// <summary>
/// 去除HTML标记
/// </summary>
/// <param name="NoHTML">包括HTML的源码 </param>
/// <returns>已经去除后的文字</returns>
public string NoHTML(string Htmlstring)
{
//删除脚本
Htmlstring = Regex.Replace(Htmlstring, @"<script[^>]*?>.*?</script>", "",
RegexOptions.IgnoreCase);
//删除HTML
Htmlstring = Regex.Replace(Htmlstring, @"<(.[^>]*)>", "",
RegexOptions.IgnoreCase);
Htmlstring = Regex.Replace(Htmlstring, @"([\r\n])[\s]+", "",
RegexOptions.IgnoreCase);
Htmlstring = Regex.Replace(Htmlstring, @"-->", "", RegexOptions.IgnoreCase);
Htmlstring = Regex.Replace(Htmlstring, @"<!--.*", "", RegexOptions.IgnoreCase);
Htmlstring = Regex.Replace(Htmlstring, @"&(quot|#34);", "\"",
RegexOptions.IgnoreCase);
Htmlstring = Regex.Replace(Htmlstring, @"&(amp|#38);", "&",
RegexOptions.IgnoreCase);
Htmlstring = Regex.Replace(Htmlstring, @"&(lt|#60);", "<",
RegexOptions.IgnoreCase);
Htmlstring = Regex.Replace(Htmlstring, @"&(gt|#62);", ">",
RegexOptions.IgnoreCase);
Htmlstring = Regex.Replace(Htmlstring, @"&(nbsp|#160);", " ",
RegexOptions.IgnoreCase);
Htmlstring = Regex.Replace(Htmlstring, @"&(iexcl|#161);", "\xa1",
RegexOptions.IgnoreCase);
Htmlstring = Regex.Replace(Htmlstring, @"&(cent|#162);", "\xa2",
RegexOptions.IgnoreCase);
Htmlstring = Regex.Replace(Htmlstring, @"&(pound|#163);", "\xa3",
RegexOptions.IgnoreCase);
Htmlstring = Regex.Replace(Htmlstring, @"&(copy|#169);", "\xa9",
RegexOptions.IgnoreCase);
Htmlstring = Regex.Replace(Htmlstring, @"(\d+);", "",
RegexOptions.IgnoreCase);
Htmlstring.Replace("<", "");
Htmlstring.Replace(">", "");
Htmlstring.Replace("\r\n", "");
Htmlstring = HttpContext.Current.Server.HtmlEncode(Htmlstring).Trim();
return Htmlstring;
}
/// <summary>
/// 使用正则表达式
/// </summary>
/// <param name="strPattern">表达式</param>
/// <param name="strText">查询文本</param>
/// <returns></returns>
private MatchCollection RexGet(string strPattern, string strText)
{
//定义一个模式字符串,不仅仅是纯文本,还可以是正则表达式
MatchCollection Matches = Regex.Matches(
strText,
strPattern,
RegexOptions.IgnoreCase | //忽略大小写
RegexOptions.ExplicitCapture | //提高检索效率
RegexOptions.Singleline
);
return Matches;
}
[Serializable]
public class WebOperation
{
public CookieContainer Cookies { get; set; }
public WebProxy Proxy { get; set; }
public int Timeout { get; set; }
public Encoding En { get; set; }
/// <summary>
/// 构造函数
/// </summary>
public WebOperation()
{
Cookies = new CookieContainer();
//设置模式
System.Net.ServicePointManager.Expect100Continue = false;
//默认时间为30秒
Timeout = 5000;
//设置默认编码
En = Encoding.Default;
}
/// <summary>
/// 打开页面
/// </summary>
/// <param name="URI"></param>
/// <returns></returns>
public string Get(string URI)
{
// 设置打开页面的参数
HttpWebRequest request = WebRequest.Create(URI) as HttpWebRequest;
request.Method = "GET";
request.KeepAlive = false;
request.CookieContainer = Cookies;
//request.UseDefaultCredentials = true;
request.Proxy = Proxy;
request.Timeout = Timeout;
// 接收返回的页面
HttpWebResponse response = request.GetResponse() as HttpWebResponse;
System.IO.Stream responseStream = response.GetResponseStream();
System.IO.StreamReader reader = new System.IO.StreamReader(responseStream, En);
string srcString = reader.ReadToEnd();
response.Close();
responseStream.Close();
reader.Close();
//返回源文件
return srcString;
}
/// <summary>
/// 获取页面的 VeiwState
/// </summary>
/// <returns></returns>
public string GetViewState(string srcString)
{
string viewStateFlag = "id=\"__VIEWSTATE\" value=\"";
int i = srcString.IndexOf(viewStateFlag) + viewStateFlag.Length;
int j = srcString.IndexOf("\"", i);
string viewState = srcString.Substring(i, j - i);
return viewState;
}
/// <summary>
/// 获取页面的 EventValidation
/// </summary>
/// <returns></returns>
public string GetEventValidation(string srcString)
{
string eventValidationFlag = "id=\"__EVENTVALIDATION\" value=\"";
int i = srcString.IndexOf(eventValidationFlag) + eventValidationFlag.Length;
int j = srcString.IndexOf("\"", i);
string eventValidation = srcString.Substring(i, j - i);
return eventValidation;
}
}
/// <summary>
/// 以Post方式打开页面
/// </summary>
/// <param name="URI"></param>
/// <param name="postData"></param>
/// <returns></returns>
public string Post(string URI, byte[] postData)
{
// 设置提交的相关参数
HttpWebRequest request = WebRequest.Create(URI) as HttpWebRequest;
request.Method = "POST";
request.KeepAlive = false;
request.ContentType = "application/x-www-form-urlencoded";
request.CookieContainer = Cookies;
request.ContentLength = postData.Length;
request.Timeout = Timeout;
//request.UseDefaultCredentials = true;
request.Proxy = Proxy;
// 提交请求数据
System.IO.Stream outputStream = request.GetRequestStream();
outputStream.Write(postData, 0, postData.Length);
outputStream.Close();
// 接收返回的页面
HttpWebResponse response = request.GetResponse() as HttpWebResponse;
Stream responseStream = response.GetResponseStream();
StreamReader reader = new System.IO.StreamReader(responseStream, En);
string srcString = reader.ReadToEnd();
foreach (Cookie cookie in response.Cookies)
{
Cookies.Add(cookie);
}
responseStream.Close();
reader.Close();
response.Close();
return srcString;
}
/// <summary>
/// 构造参数
/// </summary>
/// <param name="strName"></param>
/// <param name="strValue"></param>
/// <returns></returns>
public byte[] CreateParm(Hashtable Hash)
{
StringBuilder strParm = new StringBuilder();
foreach (DictionaryEntry item in Hash)
{
strParm.AppendFormat("{0}={1}&", item.Key, System.Web.HttpUtility.UrlEncode(item.Value.ToString()));
}
if (strParm.Length > 0)
{
strParm.Remove(strParm.Length - 1, 1);
}
// 将提交的字符串数据转换成字节数组
byte[] postData = Encoding.Default.GetBytes(strParm.ToString());
return postData;
}
/// <summary>
/// 下载图片
/// </summary>
/// <param name="URI"></param>
/// <returns></returns>
public System.Drawing.Image GetImg(string URI)
{
// 设置打开页面的参数
HttpWebRequest request = WebRequest.Create(URI) as HttpWebRequest;
request.Method = "GET";
request.Timeout = Timeout;
request.KeepAlive = false;
request.CookieContainer = Cookies;
request.Proxy = Proxy;
// 接收返回的页面
HttpWebResponse response = request.GetResponse() as HttpWebResponse;
System.Drawing.Image img = new System.Drawing.Bitmap(response.GetResponseStream());
response.Close();
//返回图片
return img;
}
接上 --------------------编程问答-------------------- 造成服务器资源100%,影响服务器运行。
麻烦各位前辈 帮忙优化下代码。
如果用最简洁的方法获取快照内容。而且不占用资源。
只要能获取快照的内容即可。其他的没特别要求。
--------------------编程问答-------------------- --------------------编程问答-------------------- 请求数据时尽量用get,与数据库交互的动作完成时记得关闭练级,释放资源。 --------------------编程问答-------------------- 字打错了,是关闭连接。 --------------------编程问答-------------------- 帮顶........... --------------------编程问答-------------------- 真的看不下去了,这多代码。 --------------------编程问答-------------------- 你是慢在了抓取内容?还是在处理内容?
建议你先把处理内容部分注释掉,以定位到底是抓取慢还是处理慢
--------------------编程问答-------------------- 应该是慢在了处理内容的代码上了,一共才请求了三次,搜索,抓取前两条快照,所以抓取处的代码应该不会导致服务器变慢 --------------------编程问答--------------------
Htmlstring = Regex.Replace(Htmlstring, @"&(quot|#34);", "\"",
RegexOptions.IgnoreCase);
Htmlstring = Regex.Replace(Htmlstring, @"&(amp|#38);", "&",
RegexOptions.IgnoreCase);
Htmlstring = Regex.Replace(Htmlstring, @"&(lt|#60);", "<",
RegexOptions.IgnoreCase);
Htmlstring = Regex.Replace(Htmlstring, @"&(gt|#62);", ">",
RegexOptions.IgnoreCase);
Htmlstring = Regex.Replace(Htmlstring, @"&(nbsp|#160);", " ",
RegexOptions.IgnoreCase);
Htmlstring = Regex.Replace(Htmlstring, @"&(iexcl|#161);", "\xa1",
RegexOptions.IgnoreCase);
Htmlstring = Regex.Replace(Htmlstring, @"&(cent|#162);", "\xa2",
RegexOptions.IgnoreCase);
Htmlstring = Regex.Replace(Htmlstring, @"&(pound|#163);", "\xa3",
RegexOptions.IgnoreCase);
Htmlstring = Regex.Replace(Htmlstring, @"&(copy|#169);", "\xa9",
RegexOptions.IgnoreCase);
Htmlstring = Regex.Replace(Htmlstring, @"(\d+);", "",
RegexOptions.IgnoreCase);
这些替换用普通的String.Replace也可以实现,所以这里别用正则
补充:.NET技术 , C#