ASP.Net中的MD5加密

System.Web.Security.HashPasswordForStoringInConfigFile() 以下是引用片段：
public string md5(string str,int code) 
{ 
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) ; 
} 
if(code==32) //32位加密 
{ 
return System.Web.Security.FormsAuthentication.HashPasswordForStoringInConfigFile(str,"MD5").ToLower(); 
} 
return "00000000000000000000000000000000"; 

}