Get the index value of an array in PHP

Question

I have an array:

$list = array(\'string1\', \'string2\', \'string3\');

I want to get the index for a given value (i.e. 1 for <

Answer 1

$find="Topsite";
$list=array("Tope","Ajayi","Topsite","Infotech");
$list_count=count($list);
sort($list);
for($i=0;$i<$list_count;$i++)
{
    if($list[$i]==$find){
         $position=$i;
    }

}
echo $position;

Answer 2

You'll have to create a function for this. I don't think there is any built-in function for that purpose. All PHP arrays are associative by default. So, if you are unsure about their keys, here is the code:

<?php

$given_array = array('Monday' => 'boring',
'Friday' => 'yay',
'boring',
'Sunday' => 'fun',
7 => 'boring',
'Saturday' => 'yay fun',
'Wednesday' => 'boring',
'my life' => 'boring');

$repeating_value = "boring";

function array_value_positions($array, $value){
    $index = 0;
    $value_array = array();
        foreach($array as $v){
            if($value == $v){
                $value_array[$index] = $value;
            }
        $index++;
        }
    return $value_array;
}

$value_array = array_value_positions($given_array, $repeating_value);

$result = "The value '$value_array[0]' was found at these indices in the given array: ";

$key_string = implode(', ',array_keys($value_array));

echo $result . $key_string . "\n";//Output: The value 'boring' was found at these indices in the given array: 0, 2, 4, 6, 7

Answer 3

This code should do the same as your new routine, working with the correct multi-dimensional array..

 $arr = array(
  'string1' => array('a' => '', 'b' => '', 'c' => ''),
  'string2' => array('a' => '', 'b' => '', 'c' => ''),
  'string3' => array('a' => '', 'b' => '', 'c' => '')
 );

 echo 'Index of "string2" = '. array_search('string2', array_keys($arr));

Answer 4

array_search should work fine, just tested this and it returns the keys as expected:

$list = array('string1', 'string2', 'string3');
echo "Key = ".array_search('string1', $list);
echo " Key = ".array_search('string2', $list);
echo " Key = ".array_search('string3', $list);

Or for the index, you could use

$list = array('string1', 'string2', 'string3');
echo "Index = ".array_search('string1', array_merge($list));
echo " Index = ".array_search('string2', array_merge($list));
echo " Index = ".array_search('string3', array_merge($list));

Answer 5

The problem is that you don't have a numerical index on your array.
Using array_values() will create a zero indexed array that you can then search using array_search() bypassing the need to use a for loop.

$list = array('string1', 'string2', 'string3');
$index = array_search('string2',array_values($list));

Answer 6

Try the array_keys PHP function.

$key_string1 = array_keys($list, 'string1');