asp.net常用函数收藏

  /// <summary>

  /// 得到站点用户IP

  /// </summary>

  /// <returns></returns>

  public static string getUserIP()

  {

  return HttpContext.Current.Request.ServerVariables["REMOTE_ADDR"].ToString();

  }

  /// <summary>

  /// 去除字符串最后一个','号

  /// </summary>

  /// <param name="chr">:要做处理的字符串</param>

  /// <returns>返回已处理的字符串</returns>

  public static string Lost(string chr)

  {

  if (chr == null || chr == string.Empty)

  {

  return "";

  }

  else

  {

  chr = chr.Remove(chr.LastIndexOf(","));

  return chr;

  }

  }

  /// <summary>

  /// 去除字符串第一个'/'号

  /// </summary>

  /// <param name="chr">要做处理的字符串</param>

  /// <returns>返回已处理的字符串</returns>

  public static string lostfirst(string chr)

  {

  string flg = "";

  if (chr != string.Empty || chr != null)

  {

  if (chr.Substring(0, 1) == "/")

  flg = chr.Replace(chr.Substring(0, 1), "");

  else

  flg = chr;

  }

  return flg;

  }

  /// <summary>

  /// 替换html中的特殊字符

  /// </summary>

  /// <param name="theString">需要进行替换的文本。</param>

  /// <returns>替换完的文本。</returns>

  public static string HtmlEncode(string theString)

  {

  theString = theString.Replace(">", ">");

  theString = theString.Replace("<", "<");

  theString = theString.Replace(" ", " ");

  theString = theString.Replace(" ", " ");

  theString = theString.Replace("\"", """);

  theString = theString.Replace("\'", "'");

  theString = theString.Replace("\n", "<br/> ");

  return theString;

  }

  /// <summary>

  /// 恢复html中的特殊字符

  /// </summary>

  /// <param name="theString">需要恢复的文本。</param>

  /// <returns>恢复好的文本。</returns>

  public static string HtmlDiscode(string theString)

  {

  theString = theString.Replace(">", ">");

  theString = theString.Replace("<", "<");

  theString = theString.Replace(" ", " ");

  theString = theString.Replace(" ", " ");

  theString = theString.Replace(""", "\"");

  theString = theString.Replace("'", "\'");

  theString = theString.Replace("<br/> ", "\n");

  return theString;

  }

  /// <summary>

  /// 生成随机数字

  /// </summary>

  /// <param name="length">生成长度</param>

  /// <returns></returns>

  public static string Number(int Length)

  {

  return Number(Length, false);

  }

  /// <summary>

  /// 生成随机数字

  /// </summary>

  /// <param name="Length">生成长度</param>

  /// <param name="Sleep">是否要在生成前将当前线程阻止以避免重复</param>

  /// <returns></returns>

  public static string Number(int Length, bool Sleep)

  {

  if (Sleep)

  System.Threading.Thread.Sleep(3);

  string result = "";

  System.Random random = new Random();

  for (int i = 0; i < Length; i++)

  {

  result += random.Next(10).ToString();

  }

  return result;

  }

  //弹出对话框

  public static void salert(string str)

  {

  HttpContext.Current.Response.Write("<script>alert('" + str + "');</script>");

  }

  /// <summary>

  /// 显示消息提示框,并回到前一页面

  /// </summary>

  /// <param name="page">当前页面指针,一般为this</param>

  /// <param name="strMsg">提示信息</param>

  public static void ShowGoHistory(System.Web.UI.Page page, string strMsg)

  {

  page.ClientScript.RegisterStartupScript(page.GetType(), "message", "<script language='javascript' defer>alert('" + strMsg.ToString() + "');window.history.go(-1);</script>");

  }

  /// <summary>

  /// 显示消息提示对话框,并进行页面跳转

  /// </summary>

  /// <param name="page">当前页面指针,一般为this</param>

  /// <param name="strMsg">提示信息</param>

  /// <param name="url"> 跳转的目标URL</param>

  public static void ShowRedirect(System.Web.UI.Page page, string strMsg, string url)

  {

  StringBuilder Builder = new StringBuilder();

  Builder.Append("<script language='javascript' defer>");

  Builder.AppendFormat("alert('{0}');", strMsg);

  Builder.AppendFormat("top.location.href='{0}'", url);

  Builder.Append("</script>");

  page.ClientScript.RegisterStartupScript(page.GetType(), "message", Builder.ToString());

  }

  //为了插入单引号

  public static string delSingle(string str)

  {

  return str.Replace("'", "''");

  }

  //由gridviw导出为Excel

  public static void ToExcel(System.Web.UI.Control ctl)

  {

  HttpContext.Current.Response.AppendHeader("Content-Disposition", "attachment;filename=Excel.xls");

  HttpContext.Current.Response.Charset = "UTF-8";

  HttpContext.Current.Response.ContentEncoding = System.Text.Encoding.Default;

  HttpContext.Current.Response.ContentType = "application/ms-excel";//image/JPEG;text/HTML;image/GIF;vnd.ms-excel/msword

  ctl.Page.EnableViewState = false;

  System.IO.StringWriter tw = new System.IO.StringWriter();

  System.Web.UI.HtmlTextWriter hw = new System.Web.UI.HtmlTextWriter(tw);

  ctl.RenderControl(hw);

  HttpContext.Current.Response.Write(tw.ToString());

  HttpContext.Current.Response.End();

  }

  ///using System.Security.Cryptography;

  ///using System.Text;

  /// <summary>

  /// MD5函数

  /// </summary>

  /// <param name="str">原始字符串</param>

  /// <returns>MD5结果</returns>

  public static string MD5(string str)

  {

  byte[] b = Encoding.Default.GetBytes(str);

  b = new MD5CryptoServiceProvider().ComputeHash(b);

  string ret = "";

  for (int i = 0; i < b.Length; i++)

  ret += b[i].ToString("x").PadLeft(2, '0');

  return ret;

  }

  ///using System.Net;

  ///using System.IO;

  /// <summary>

  /// 根据Url获得源文件内容

  /// </summary>

  /// <param name="url">合法的Url地址</param>

  /// <returns></returns>

  public static string GetSourceTextByUrl(string url)

  {

  WebRequest request = WebRequest.Create(url);

  request.Timeout = 20000;//20秒超时

  WebResponse response = request.GetResponse();

  Stream resStream = response.GetResponseStream();

  StreamReader sr = new StreamReader(resStream);

  return sr.ReadToEnd();

  }