(PHP 5 >= 5.1.0, PHP 7)
SplFileObject::fwrite — Write to file
$str
[, int $length
] )
Writes the contents of string to the file
strThe string to be written to the file.
length
If the length argument is given, writing will
stop after length bytes have been written or
the end of string is reached, whichever comes
first.
Returns the number of bytes written, or NULL on error.
Example #1 SplFileObject::fwrite() example
<?php
$file = new SplFileObject("fwrite.txt", "w");
$written = $file->fwrite("12345");
echo "Wrote $written bytes to file";
?>
以上例程的输出类似于：
Wrote 5 bytes to file