private bool RemoveUserFromGroup(string sGoupName, string sUserLoginName)

    {

        bool res = false;

        try

        {

            SPWeb web = SPContext.Current.Web;

            SPGroup oGroup = web.SiteGroups[sGoupName];

            SPUser oUser = GetSPUser(sUserLoginName);

            if (oUser != null)

            {

                web.AllowUnsafeUpdates = true;

                oGroup.RemoveUser(oUser);

                oGroup.Update();

                res = true;

                web.AllowUnsafeUpdates = false;

            }

        }

        catch (Exception ex)

        {

            string sMessage = ex.Message;

            //throw;

        }

        return res;

    }

    private bool RemoveUserFromGroup(SPGroup oGroup, SPUser oUser)

    {

        bool res = false;

        try

        {

            SPWeb web = SPContext.Current.Web;

            if (oUser != null&&oGroup!=null)

            {

                web.AllowUnsafeUpdates = true;

                oGroup.RemoveUser(oUser);

                oGroup.Update();

                res = true;

                web.AllowUnsafeUpdates = false;

            }

        }

        catch (Exception ex)

        {

            string sMessage = ex.Message;

            //throw;

        }

        return res;

    }

    private SPUser GetSPUser(string sLoginName)

    {

        SPUser oUser = null;

        try

        {

            if (!string.IsNullOrEmpty(sLoginName))

            {

                oUser = SPContext.Current.Web.EnsureUser(sLoginName);

            }

        }

        catch (Exception ex)

        {

            string sMessage = ex.Message;

        }

        return oUser;

    }

    private void RemoveUser(string sLoginName)

    {

        SPUser oUser = GetSPUser(sLoginName);

        if (oUser!=null)

        {

            SPGroupCollection groups = oUser.Groups;

            if (groups!=null&&groups.Count>)

            {

                foreach (SPGroup g in groups)

                {

                    RemoveUserFromGroup(g, oUser);

                }

            }

        }

    }

    private bool AddUserIntoGroup(string sGroupName, string sUserLoginName)

    {

        bool res = false;

        try

        {

            SPWeb web = SPContext.Current.Web;

            web.AllowUnsafeUpdates = true;

            SPGroup oGroup = web.SiteGroups[sGroupName];

            SPUser oUser = GetSPUser(sUserLoginName);

            if (oUser != null)

            {

                oGroup.AddUser(oUser);

                oGroup.Update();

                res = true;

            }

            web.AllowUnsafeUpdates = false;

        }

        catch (Exception ex)

        {

            string sMessage = ex.Message;

            //throw;

        }

        return res;

    }

    private string FilterSPUserString(string str)

    {

        if (string.IsNullOrEmpty(str))

        {

            return str;

        }

        if (str.IndexOf(";#") > )

        {

            str = str.Substring(str.LastIndexOf(";#") + );

        }

        return str;

    }

    private bool CreateSiteGroup(string sGroupName, string sGroupDescription)

    {

        bool res = false;

        using (SPWeb oWebsiteRoot = SPContext.Current.Site.RootWeb)

        {

            oWebsiteRoot.AllowUnsafeUpdates = true;

            SPGroupCollection collGroups = oWebsiteRoot.SiteGroups;

            string sLoginName = SPContext.Current.Web.CurrentUser.LoginName;

            SPUser oUser = oWebsiteRoot.Users[sLoginName];

            SPMember oMember = oWebsiteRoot.Users[sLoginName];

            collGroups.Add(sGroupName, oMember, oUser, "Description");

            oWebsiteRoot.AllowUnsafeUpdates = false;

            res = true;

        }

        return res;

    }

    /// <summary>

    /// 给组赋权限

    /// </summary>

    /// <param name="sGroupName"></param>

    /// <param name="sPermissionLever"></param>

    /// <returns></returns>

    private bool SetGroupPermission(string sGroupName, string sPermissionLever)

    {

        bool res = false;

        using (SPWeb oWebsiteRoot = SPContext.Current.Site.RootWeb)

        {

            oWebsiteRoot.AllowUnsafeUpdates = true;

            SPRoleAssignment roleAssignment = new SPRoleAssignment(oWebsiteRoot.SiteGroups[sGroupName]);

            roleAssignment.RoleDefinitionBindings.Add(oWebsiteRoot.RoleDefinitions[sPermissionLever]);

            oWebsiteRoot.Update();

            oWebsiteRoot.AllowUnsafeUpdates = false;

            res = true;

        }

        return res;

    }

    private void DeleteSiteGroup(SPWeb web, string groupName)

    {

        web.AllowUnsafeUpdates = true;

        SPGroupCollection groups = web.SiteGroups;

        groups.Remove(groupName);

        web.Update();

        web.AllowUnsafeUpdates = false;

    }