📅 最后修改于: 2020-09-28 04:54:19 🧑 作者: Mango
PHPfopen()函数用于打开文件或URL并返回资源。fopen()函数接受两个参数：$filename和$mode。$filename表示要打开的文件，$mode表示文件模式，例如只读，读写，只写等。
句法
resource fopen ( string $filename , string $mode [, bool $use_include_path = false [, resource $context ]] )
| Mode | Description |
|---|---|
| r | Opens file in read-only mode. It places the file pointer at the beginning of the file. |
| r+ | Opens file in read-write mode. It places the file pointer at the beginning of the file. |
| w | Opens file in write-only mode. It places the file pointer to the beginning of the file and truncates the file to zero length. If file is not found, it creates a new file. |
| w+ | Opens file in read-write mode. It places the file pointer to the beginning of the file and truncates the file to zero length. If file is not found, it creates a new file. |
| a | Opens file in write-only mode. It places the file pointer to the end of the file. If file is not found, it creates a new file. |
| a+ | Opens file in read-write mode. It places the file pointer to the end of the file. If file is not found, it creates a new file. |
| x | Creates and opens file in write-only mode. It places the file pointer at the beginning of the file. If file is found, fopen() function returns FALSE. |
| x+ | It is same as x but it creates and opens file in read-write mode. |
| c | Opens file in write-only mode. If the file does not exist, it is created. If it exists, it is neither truncated (as opposed to ‘w’), nor the call to this function fails (as is the case with ‘x’). The file pointer is positioned on the beginning of the file |
| c+ | It is same as c but it opens file in read-write mode. |