PHP超全局数组的长度

Question

是否可以使用某种length（）或size（）检查$ _FILES []中有多少个项目？

Answer 1

It's a normal array besides the fact that it's superglobal - simply use count($_FILES) .

To count the successfully uploaded files, you could do the following in PHP5.3:

$successCount = array_reduce($_FILES, function($val, $file) {
    if($file['error'] == UPLOAD_ERR_OK) return $val + 1;
    return $val;
}, 0);

In older PHP versions the easiest way (I consider string function names for callbacks ugly) would be using a simple loop:

$count = 0;
foreach($_FILES as $file) {
    if($file['error'] == UPLOAD_ERR_OK) $count++;
}

Answer 2

count（）函数可以做到这一点： http : //php.net/manual/en/function.count.php

$c = count($_FILES);

Answer 3

there are 2 ways in naming fields for the upload.
While filename[] will make this array messy, filename1 , filename2 etc will make $_FILES array behave as you expected and count($_FILES) will return number of input fields

If you don't know array structure, you should use print_r($_FILES) to see it first and then decide, what you want to count.

Also note that array name is $_FILES , not $_FILES[] as you mentioned. It's operator, not array name.