本文实例讲述了php实现以只读方式打开文件的方法。分享给大家供大家参考。具体分析如下:
php中可以通过fopen()打开一个文件,第二个参数设置为"r"表示已只读方式打开,函数返回一个文件句柄,其它函数就可以通过这个文件句柄对文件进行不同方式的读取
<?php $file = fopen("/tmp/file.txt", "r"); print("Type of file handle: " . gettype($file) . "\n"); print("The first line from the file handle: " . fgets($file)); fclose($file); ?>
上面的代码返回如下结果
Type of file handle: resource
The first line from the file handle: Welcome to sharejs.com php tutorials
文件读取完成后,需要使用fclose()函数关闭文件句柄,以释放资源
希望本文所述对大家的php程序设计有所帮助。

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