PHP in_array（如果只有此项）

Question

I am using in_array to detect if a value is within a PHP array, my array looks like this...

$fruits = array("banana", "grape", "orange", "apple");

/* is grape in the array */
if (in_array('grape', $fruits)) {
    echo 'Grape Detected';
} else {
    echo 'Grape not detected';
}

I am trying to modify this so that it can also detect when the 'grape' is the only item in the array, so if the array looked like this...

$fruits = array("grape", "grape", "grape");

or...

$fruits = array("grape");

Then I could display a custom message, anyone have an example I can see?

Answer 1

Check if there isn't more than one element, and if it matches your condition.

if(count($fruits) === 1 && in_array('grape', $fruits)) {
    echo "There's only one fruit here, and it's a grape!";
}

EDIT:

You can check if 'grape' is the only thing in the array and also how many of it are there that way:

$condition_met = false;
foreach ($fruits as &$iterator) {
    if($iterator !== 'grape') {
        $condition_met = true;
    }
}

if($condition_met === false)
{
    echo 'There are only grapes in this fruits basket! There are ' . count($fruits) . ' unique beauties!';
}

Answer 2

To display custom message only when 'grape' is the only fruit in the list you can do it by changing your code to:

/* is grape in the array */
if (in_array('grape', $fruits)) {
    if (count(array_unique($fruits)) === 1) {
        echo 'Grape is the only fruit in the list';
    } else {
        echo 'Grape detected';
    }
} else {
    echo 'Grape not detected';
}

Answer 3

Here is the simplest way to do that:

if (array_unique($fruits) === array('grape')) {
    echo 'Grape Detected';
}

Explanation: array_unique removes all duplicate values from an array. If "grape" is the only item in the array, the result of array_unique($fruits) should be equal to array('grape') . The === operator checks that both values are arrays and they both have the same elements.

Answer 4

Try this,

Using array_count_values in-built function.

<?php
$fruits = array("banana", "grape", "orange", "apple","grape", "grape",     "grape");
$tmp_fruits = array_count_values($fruits);
/* is grape in the array */
foreach($tmp_fruits as $fruit=>$total){
    echo $fruit." Detected ".$total." Times."."<br />";
}
?>

Answer 5

You can use the function array_count_values() . This will return a new array with the number of times an item was repeated.

<?php
    $fruits = array("grape", "grape", "grapr");

    $vals = array_count_values($fruits);
    echo 'Unique Items: '.count($vals).'<br><br>';
    print_r($vals);
?>

Will output:

Unique Items: 2

Array ( [grape] => 2 [grapr] => 1 ) //Shows the item in the array and how many times it was repeated

You can then loop through the new array, $vals , to find out how many times an item was repeated and display the corresponding message.

Hopefully it helps you out.

Answer 6

Here's a check that is true if:

• Array only has 'Grape'
• Regardless of whether or not there are multiple 'Grape' entries

$uniqueFruits = array_unique($fruit);

if (count($uniqueFruits) == 1 && $uniqueFruits[0] == 'grape') {
     // Only 'grape' in here
} elseif() {
  // Some other check
} else {
  // Otherwise
}