关于泛型的查找方式

namespace CSWave.Core.Security
{
    using CSWave.Core;
    using CSWave.Core.Business;
    using CSWave.Core.Component;
    using CSWave.Framework.Utility;
    using System;

    public static class Authentication
    {
        public static UserGroup FindGroupById(int groupId)
        {
            return UserGroupBiz.Current.Find(delegate (UserGroup item) {
                return item.Id == groupId;
            });
        }

        public static UserRole FindRoleByGroupId(int groupId)
        {
            UserGroup group = FindGroupById(groupId);
            if (group == null)
            {
                return null;
            }
            return FindRoleByRoleId(group.RoleId);
        }

        public static UserRole FindRoleByRoleId(int roleId)
        {
            return UserRoleBiz.Current.Find(delegate (UserRole item) {
                return item.Id == roleId;
            });
        }

        public static void HasPermission(ManageTaskType task, AdminAccount user)
        {
            if (!HasPermissionAsBoolen(task, user))
            {
                EXM.Throw(ErrorType.AuthenticationRequest, true);
            }
        }

        public static void HasPermission(UserTaskType task, UserAccount user)
        {
            if (!HasPermissionAsBoolen(task, user))
            {
                EXM.Throw(ErrorType.AuthenticationRequest, true);
            }
        }

        public static bool HasPermissionAsBoolen(ManageTaskType task, AdminAccount user)
        {
            if ((user == null) || (user.Id < 1))
            {
                HttpUtility.Redirect("/Manage/Login.aspx");
                return false;
            }
            bool flag = false;
            int taskFlag = (int) task;
            UserRole role = FindRoleByGroupId(user.GroupId);
            if (role != null)
            {
                flag = PermissionCompare(role, taskFlag);
            }
            if (!flag)
            {
                UserGroup group = FindGroupById(user.GroupId);
                if ((group != null) && (group.ParentId != 0))
                {
                    flag = PermissionCompare(FindRoleByGroupId(group.ParentId), taskFlag);
                }
            }
            return flag;
        }

        public static bool HasPermissionAsBoolen(UserTaskType task, UserAccount user)
        {
            return HasPermissionAsBoolen(task, user.GroupId);
        }

        public static bool HasPermissionAsBoolen(UserTaskType task, int groupId)
        {
            int flag = (int) task;
            return HasPermissionAsBoolen(flag, groupId);
        }

        public static bool HasPermissionAsBoolen(int flag, int groupId)
        {
            bool flag2 = false;
            UserRole role = FindRoleByGroupId(groupId);
            if (role != null)
            {
                flag2 = PermissionCompare(role, flag);
            }
            if (!flag2)
            {
                UserGroup group = FindGroupById(groupId);
                if ((group != null) && (group.ParentId != 0))
                {
                    flag2 = PermissionCompare(FindRoleByGroupId(group.ParentId), flag);
                }
            }
            return flag2;
        }

        public static bool PermissionCompare(UserRole role, int taskFlag)
        {
            if (role == null)
            {
                return false;
            }
            return (role.Permission.IndexOf(string.Format(",{0},", taskFlag)) >= 0);
        }
    }
}