asp.net常用函数收藏

主要包括 得到站点用户IP,去除字符串最后一个','号、去除字符串第一个'/'号等/// < 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;
}
主要包括 得到站点用户IP,去除字符串最后一个','号、去除字符串第一个'/'号等
//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();
}