property UserPermissions: LongWord; // read only
property UserGrantedPermissions: TPdfPermissions; // read only
function UserHasPermission(Permission: TPdfPermission): Boolean;
UserPermissions 返回打开文档所用的密码对应的有效权限掩码
UserGrantedPermissions 将该掩码解码为 TPdfPermissions,而 UserHasPermission 直接测试一个 TPdfPermission 值
当文档使用所有者密码打开时,用户权限集与所有者权限集通常相等
GrantedPermissions 和 HasPermission
if not Pdf1.UserHasPermission(permPrint) then
DisablePrintCommands;