为什么VS里面报错没改任何代码，再次运行又能正常运行

[哎算了]

MD5.CS

using System;
using System.Data;
using System.Web.Security;


namespace Myjiami

{
    public class MyFM
    {
		public static string GetMD5Hash(string str,int code) //MD5加密
		{
		 if(code==16) //16位MD5加密（取32位加密的9~25字符） 
		   { 
			return System.Web.Security.FormsAuthentication.HashPasswordForStoringInConfigFile(str,"MD5").ToLower().Substring(8,16) ; 
		   }  
		   else//32位加密 
		   { 
			return System.Web.Security.FormsAuthentication.HashPasswordForStoringInConfigFile(str,"MD5").ToLower(); 
		   }  
		}
		
		
	public static string FilterSql(string source)//过滤安全字符
        {
		        source = source.ToLower();
                        source = source.Replace("'", "");
                        source = source.Replace("\"", "");
			source = source.Replace("/", "");
                        source = source.Replace("|", "");
                        source = source.Replace(";", "");
			source = source.Replace(":", "");
                        source = source.Replace("(", "");
                        source = source.Replace(")", "");
			source = source.Replace("%", "");
			source = source.Replace("&", "");
			source = source.Replace("?", "");
			source = source.Replace("+", "");
			source = source.Replace("^", "");
			source = source.Replace("--", "");
			source = source.Replace("<", "");
			source = source.Replace(">", "");
			source = source.Replace("{", "");
			source = source.Replace("}", "");
			source = source.Replace("[", "");
			source = source.Replace("]", "");
			source = source.Replace("]", "");
                        source = source.Replace("=", "");
                        source = source.Replace("select", "");
			source = source.Replace("where", "");
			source = source.Replace("cmd", "");
			source = source.Replace("from", "");
			source = source.Replace("and", "");
                        source = source.Replace("or", "");
                        source = source.Replace("execute", "");
                        source = source.Replace("xp_", "");
                        source = source.Replace("sp_", "");
			source = source.Replace("Chr(34)", "");
			source = source.Replace("Chr(0)", "");
            source = source.Replace("0x", "");//防止16进制注入
            return source;
        }

    }
	
}

using Myjiami;//引入MD5.cs加密
 string password1 = Myjiami.MyFM.GetMD5Hash(context.Request["password"].ToString(),16);

这行代码在ASHX里对密码进行加密，VS老报错，说Myjiami未找到上下文，但是我再次运行又能运行，是我命名不对，还是VS敏感?

[threenewbee]

到底是编译错误还是运行错误，这代码似乎不会丢出运行错误，除非输入参数是null

[哎算了]

引用 2 楼 贵阳老马马善福专业维修游泳池堵漏防水工程 的回复:

到底是编译错误还是运行错误，这代码似乎不会丢出运行错误，除非输入参数是null

你说的好像有点对，ajax传入的验证码，好像有时候会NULL,但是我不知道为什么会丢了

[huodexiangtiaogou123]

这样看不出来啥错误 或许是你不小心改了什么东西，然后有改回来了