Removing key => value pairs from an array, but its not removing them

问题

I am trying to remove two key value pairs from an array, I am using the code below to segregate out the keys I don't want. I don't understand why it is not equating properly. if I remove the OR (|| $key != 6) it will work properly but I was hoping to have one if statement. Can anyone explain what I'm doing wrong? Thanks.

$test = array( '1' => '21', '2' => '22', '3' => '23', '4' => '24', '5' => '25', '6' => '26'  );

foreach( $test as $key => $value ) {
    if( $key != 4 || $key != 6 ) {
        $values[$key] = $value;
        echo '<br />';
        print_r( $values );
    }
}

// Output
Array ( [1] => 21 [2] => 22 [3] => 23 [4] => 24 [5] => 25 [6] => 26 )

回答1:

This is the best way to do that:

$values = $test;
unset($values[4], $values[6]);

Assuming that you need a new array $values. Otherwise remove them directly from $tests.

Reference here: http://php.net/unset

The following is just for your own education in boolean logic, it's not the way you should do it.

You need to change || to &&. You don't want either in the result. With logical OR, all of them will get through because 4 != 6 and 6 != 4. If it hits 4, it will run like this:

Are you not equal to 4? Oh, you are equal to 4? Well, the best I can do is let you though if you're not equal to 6.

If you change it to &&, it will run something like this:

Are you a number besides 4 or 6? No? Sorry pal.

回答2:

Someone's tripped over De Morgan's laws again...

if( $key != 4 && $key != 6 ) {

回答3:

Assuming you don't really need the loop, this will do the same thing:

unset($test[4], $test[6])

回答4:

Your condition is wrong. if you dont want to take key 4 and 6 then your condition should be like this

foreach( $test as $key => $value ) {
   if( $key != 4 && $key != 6 ) {

回答5:

There is a native PHP function:

$values = array_diff_key ($test , array('4'=>'','6'=>''));

来源：https://stackoverflow.com/questions/7035332/removing-key-value-pairs-from-an-array-but-its-not-removing-them

标签

php

array-unset