PHP/Data Structure/count
Версия от 10:37, 26 мая 2010; (обсуждение)
Содержание
Counting Array Elements
<?php
$dogs = array("A" => "AA", "Bud" => "BB", "C" => "D");
$birds = array("parrot", "magpie", "lorakeet", "cuckoo");
printf("<p>There are %d dogs and %d birds.</p>", count($dogs), count($birds));
$birds[] = "ibis";
printf("<p>There are %d birds:</p>", count($birds));
printf("<pre>%s</pre>\n", var_export($birds, TRUE));
$birds[10] = "heron";
unset($birds[3]);
printf("<p>There are %d birds:</p>", count($birds));
printf("<pre>%s</pre>\n", var_export($birds, TRUE));
?>
Get the size of an array in PHP using the count() function
<?php
$dogs = array("A" => "C", "B" => "D", "X" => "Z");
$birds = array("a", "b", "c", "d");
printf("%d dogs and %d birds", count($dogs), count($birds));
$birds[] = "i";
printf("%d birds:", count($birds));
printf("%s", var_export($birds, TRUE));
$birds[10] = "h";
unset($birds[3]);
printf("%d birds:", count($birds));
printf("%s", var_export($birds, TRUE));
?>
Getting the Number of Lines in a File
<?php
$afile = "data.txt";
if (file_exists ($afile)){
$rows = file ($afile);
echo count ($rows) . " lines in this file"; //Outputs 4 in this case
} else {
echo "Sorry, file does not exist.";
}
?>
Using count() to Iterate Through an Array
<?php
$myarray = array("php", "is", "cool");
for($i = 0; $i < count($myarray); $i++) {
echo "The value of index $i is: {$myarray[$i]}<BR>\n";
}
?>