本文实例总结了C#常见应用函数。，具体如下：
1、页面写CS代码（代码内嵌）
<%@ Import Namespace="System" %>
<%@ Import Namespace="System.Collections.Generic" %>
<Script runat="server">
public int userId = 0;
protected void Page_Load(object sender, EventArgs e)
{
userId =Convert.ToInt32(Request.QueryString["UserID"]);
Response.Write(userId);
}
</Script>
<%
if (userId > 0){
msg = "欢迎登录!";
}
else {
msg = "未找到用户";
}
%>
<%= this.msg %>
2、获取时间间隔
/// <summary>
/// 获取时间间隔（模拟微博发布文章的时间间隔）
/// </summary>
/// <param name="date"></param>
/// <returns></returns>
public string GetDateStr(DateTime date)
{
if (date < DateTime.Now)
{
TimeSpan ts = DateTime.Now - date;
if (ts.TotalHours < 1 && ts.TotalMinutes < 1)
{
return "1分钟前";
}
else if (ts.TotalHours < 1 && ts.TotalMinutes > 0)
{
return Convert.ToInt32(ts.TotalMinutes) + "分钟前";
}
else if (ts.TotalHours < 4)
{
return Convert.ToInt32(ts.TotalHours) + "小时前";
}
else if (DateTime.Now.Date == date.Date)
{
return date.ToString("HH:mm");
}
else
{
return date.ToString("yyyy-MM-dd");
}
}
return date.ToString("yyyy-MM-dd");
}
3、遍历Url中的参数列表
/// <summary>
/// 遍历Url中的参数列表
/// </summary>
/// <returns>如:(?userId=43&userType=2)</returns>
public string GetUrlParam()
{
string urlParam = "";
if (Request.QueryString.Count > 0)
{
urlParam = "?";
NameValueCollection keyVals = Request.QueryString;
foreach (string key in keyVals.Keys)
{
urlParam += key + "=" + keyVals[key] + "&";
}
urlParam = urlParam.Substring(0, urlParam.LastIndexOf('&'));
}
return urlParam;
}
4、清除文本HTML码
using System.Text.RegularExpressions;
/// <summary>
/// 清除文本HTML码
/// </summary>
public string RemoveHtmlTag(string htmlStr)
{
if (string.IsNullOrEmpty(htmlStr))
return string.Empty;
return Regex.Replace(htmlStr, @"<[^>]*>", "");
}
5、反射 通过类名创建类实例
using System.Reflection;
/// <summary>
/// 反射 通过类名创建类实例
/// </summary>
public void ReflecTest()
{
Object objClass = Assembly.GetExecutingAssembly().CreateInstance("MyStudy.BLL.BookInfoBLL"); //参数：类的完全限定名，无需类的后缀名
if (objClass != null)
{
BookInfoBLL bll = (BookInfoBLL)objClass;
}
}
