15c02-1.php

来自「介绍PHP5的给类型函数应用」· PHP 代码 · 共 47 行

<?php
// We are going to read/write from a file that has the following format:
// line 1 will be a 7 digit number (zero padded) followed immediately by
//    a string of any length.
// line 2 will be a 3 character code, followed by *, then a left-justified
//    string no longer than 40 characters, a space, and then a float value

// Define the data that we will be writing:
$num = 27;
$str = 'An entry into this data file';
$code = 'AxH';
$left = 'Data Validated';
$val = 5.6789;

// Now open a data file to write these out to:
$dat = fopen('test.dat', 'w');

// And put this data into it in the custom format described:
// First line, a zero padded 7 digit number followed immediately by a string
fprintf($dat, "%07d%s\n", $num, $str);

// Second line, 3 character code, *, 40 char left-just string, space, float
fprintf($dat, "%3s*%-40s %f\n", $code, $left, $val);

// Now close the file.
fclose($dat);

// Now let's dump the file to the screen to see what it looks like:
echo "<pre>File Contents:\n";
readfile('test.dat');

// Now let's open it back up to read from it:
$readdat = fopen('test.dat', 'r');
echo "\n\nFile Data:\n";

// Read back in the first line using a similar format string.
fscanf($readdat, "%07d%[^\n]", $n1, $s2);
echo "Number = '{$n1}'\nString = '{$s2}'\n";

// And now the second line:
fscanf($readdat, "%3s*%40[^\n] %f\n", $c3, $l4, $v5);
echo "Code = '{$c3}'\nLeft-String = '{$l4}'\nFloat = '{$v5}'";
echo "</pre>";

// Close the file:
fclose($readdat);
?>