Hello, everyone. Here is the video tutorial of Pip provided by Beifeng and the ladybug external club. I'm Tu Jiang's teacher, Li Yanhui. Today, we will continue to look at the sixth chapter of the directory and documents. We have finished reading the documents in the last class. So in this class, we will talk about some of the remaining knowledge and directory operations, er, In the last lesson, we directly talked about the method of circulation, and then printed out all the files by byte by byte. Right, OK, let's talk about one to check whether the file exists. What's the use of this function? Let's take a look. OK, sometimes, sometimes, when doing programs, If the file does not exist, it can never be operated. Of course, as we said before, like f open, if the file does not exist, we will automatically create it, but when it is automatically created, it is empty. So in some cases, you can use it only when there is data. Well, for example, when reading a file, What must you do to ensure that this file must exist before you can operate
Suitable for people
It is suitable for beginners of PHP, and hopes to develop general enterprise functional websites after rapid learning!
You will learn
[Teacher Li Yanhui's first PHP video tutorial] This quarter's course can learn the basic knowledge of PHP, and learn to use process oriented thinking to create a multi-user message system!
Course Introduction
Course objectives ：
[Teacher Li Yanhui's first PHP video tutorial] This quarter's course can learn the basic knowledge of PHP, and learn to use process oriented thinking to create a multi-user message system!
Suitable for:
It is suitable for beginners of PHP, and hopes to develop general enterprise functional websites after rapid learning!
Learning conditions:
But you need to have the xhtml course foundation, and have better experience in learning programming languages, such as C language, VB language, etc!
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