Oh, it is dangerious to play basketball with eyeglasses. Although the eyeglasses help you see better, but they may slipping down from your nose when you move your body. Besides, if there are basketball hit your head/eyes, it may cause damages for both eyeglasses and your eyes. If you have really bad vision, you can buy prescription sports glasses that made of polycarbnate materials so that to provide your well protection and vision aids.
If you wear glasses, why not choose basketball glasses when you play basketball? In fact, basketball glasses are especially made for people engage in the games. If you need vision aids, prescription basketball glasses are available that can give you vision correction. What's more, the glasses made of strong polycarbonate lenses that can protect the eyes from the hitting by the balls or other players by accident. Hope this helps.
You should protect yourself, and not play too fierce. When you have a physical confrontation, so long as you do not wave your elbow, your glasses can not be attacked. But you'd better not wear your glasses while playing basketball, because it is easy to break and hurt your eyes. If you are very short-sighted, without glasses, you can not see the basketball, I suggest you prepare two pairs of glasses, one pair is used in your daily life, and another is used while playing basketball, you should buy a pair of prescription basketball glasses, which can protect your eyes. You can search basketball glasses in Google, there have different designs.
A lot of people wear glasses when playing basketball, for the purpose of protecting your glasses, you need to make sure you have a band that goes behind your head and connects with the glasses to prevent them from falling off, and if possible with your money situation try and buy sports goggles to wear or contacts.
Well, to be honest with you, you got the relationship all upside down. It should be that your glasses should be protecting your eyes, not that you should look after them glasses. The best way to do so,I think, is to get your hands on a pair of sports protection glasses. Especially in sports with fierce confrontations like basketball.As a matter of fact, there are specially designed basketball protecitve glasses out there on the market that you can purchase. With them on your face, you will never worry about the possibilities of getting hurt.