How to find min value and its associative key in an array

Question

I'm trying to get the key and value of an array which has min value. Here is my code. I have empty value variables I want the values which are not empty and from the values, i need a key and the value which is min from an array or any other mode if possible.

 <?php
      $serial_sale_price    ='2';
        $promo_sale_price   ='';
        $inv_sale_price     ='300.00';
        $price_search_seq = 'B';
        //validate for 0 values
        if($serial_sale_price!='' && $serial_sale_price==0)
        {
            $serial_sale_price='0.00';
        }
        if($promo_sale_price!='' && $promo_sale_price==0)
        {
            $promo_sale_price='0.00';
        }
        if($inv_sale_price!='' && $inv_sale_price==0)
        {
            $inv_sale_price='0.00';
        }


        $remove_empty = array('S'=>$serial_sale_price,
                               'P'=>$promo_sale_price, 
                               'I'=>$inv_sale_price);
        $find_min = array_filter($remove_empty); // Array which required in 
        echo "<pre>";
        print_r($find_min);
        $sale_price =  min($find_min);//Minimum Price for the array 
        $price_rule = '';//here i want to get the key which have min value

        echo "sales price:$sale_price,price_rule:$price_rule";

How to get the key of min value and key of the min value at a time. what i'm expecting from my example. if min value is serial_sales_price then key is 'S' and value is 2

Answer 1

// Sample by PHP Method 

$var = array_keys($remove_empty , min($remove_empty ));
//$var[0] for letest key have minimum value.    

//This function returns the key for the minimum value. 

function getMinKey( $array )
{
    $min = 0;
    $key = '';
    foreach( $array as $k => $v )
    {
        $min = min($array);
    }
    foreach( $array as $k => $v )
    {

        if($min == $v)
        {
            $key = $k;
        }


    }
    return $key;
}

  echo getMinKey($remove_empty); // for min value key;