streamWrapper::stream_read

(PHP 4 >= 4.3.2, PHP 5, PHP 7)

streamWrapper::stream_read — Read from stream

说明

public streamWrapper::stream_read ( int $count ) : string

This method is called in response to fread() and fgets().

Note:

Remember to update the read/write position of the stream (by the number of bytes that were successfully read).

参数

count

How many bytes of data from the current position should be returned.

返回值

If there are less than count bytes available, return as many as are available. If no more data is available, return either FALSE or an empty string.

错误／异常

调用此方法失败将给出 E_WARNING（未实现）。

Note:

If the return value is longer then count an E_WARNING error will be emitted, and excess data will be lost.

注释

Note:

streamWrapper::stream_eof() is called directly after calling streamWrapper::stream_read() to check if EOF has been reached. If not implemented, EOF is assumed.

Warning

When reading the whole file (for example, with file_get_contents()), PHP will call streamWrapper::stream_read() followed by streamWrapper::stream_eof() in a loop but as long as streamWrapper::stream_read() returns a non-empty string, the return value of streamWrapper::stream_eof() is ignored.

参见

  • fread() - 读取文件（可安全用于二进制文件）
  • fgets() - 从文件指针中读取一行