Recently, I took a closer look at the function part of PHP. When I didn't look at it before, I didn't feel much about it, but now I realize that if I want to truly understand all the functions of PHP, I'm afraid it won't take a day! Although the functions provided by PHP are not the richest, the number is quite large, the functions are very powerful, and the scope is very wide. If you want to truly master it, in addition to the knowledge of PHP itself, you also need a lot of related networks. knowledge etc. But if you really have the patience to conquer each function one by one, I believe you will benefit a lot.
Okay, here is some of my experience and learning summary during the learning process. Let’s discuss it with everyone. I wonder if it will be helpful to everyone’s learning!
Currently, based on PHP4, the latest online manual includes a total of 76 categories of function libraries, and each category has a different number of specific functions. There are so many functions. When I first started, I was confused. I didn’t understand many functions! Slowly, for the convenience of learning, I divided these functions into the following categories:
1. Common PHP functions: This type of function should basically be what you have after installing PHP by default. You can use it immediately, including mathematical functions, string functions, etc. There are similar functions in many other languages. People who have some programming experience should not find it difficult to learn.
2. Functions that interact with database management systems: Anyone who has read the preface of the PHP manual should know that PHP supports a large number of database systems, and the interaction between PHP and these database systems is completed through a batch of functions. Although PHP supports many databases, the methods of operating databases through PHP are basically the same, and the programming ideas are also similar. So you can choose one of them to learn according to your own situation. After learning one, you can basically master the other function libraries. Of course, there may be some subtle differences, but I think with the experience of the first database, the other function libraries It should be no problem for you.
3. Extended or very commonly used functions: These functions are divided into two categories: one is supported only when compiling PHP with relevant compilation options. The other is designed to support some other companies' products, so if you want to use it, you also need support and knowledge of related products.
Through the above classification, I think we should follow the above classification order when learning. First master all the basic operating functions. They may also be used in your future study. This part should It’s not very difficult, and after learning it, it will give you the confidence to continue learning! Then learn the database function library. The realization of dynamic web pages depends to a large extent on the application of the database system. If you don't know how to use PHP to control the database, then I can only say that you haven't learned PHP yet. So how should we do so many functions? Choose one of them. Due to the absolute combination of MySQL and PHP, I think you should use it as a starting point, and you can learn it in a windows environment. You can work and study at the same time, so why not? Finally, let’s learn the third type of functions. Of course, you may not need to learn them, because these are generally only needed to solve special problems. If you want to learn, of course no one will stop you, but when learning this part of the function, I am afraid you will also need a lot of other related knowledge, such as: Linux, XML, etc. Only in this case can you truly understand what you are doing, how to debug your program, and analyze whether your program is executed correctly.
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