如果输入的数据是关键值，则检查并返回关联数组中的键值

Question

我从数据库中获取我无法控制的信息。 “状态”的值是用户输入的（并且被正确清理的）值，但可以是写出的状态名称或两个字母的邮政缩写。我可以轻松地构建一个状态和缩写的关联数组。但我想知道是否有一种方法，PHP来确定一个值是否在状态数组中/缩写为键或值。所以，如果你输入“CA”，它会看到它是一个有效的两个字母键并返回它。如果它看到“XY”不是有效的键那么它会回退默认的“OTHER”键（ZZ），但是如果用户输入的输入是“New York”，它将看到它是有效的值并返回关联密钥“NY”？

Answer 1

$userInput; // Your user's input, processed using regex for capitals, etc to match DB values for the strings of the states. 
// Otherwise, do your comparisons in the conditions within the loop to control for mismatching capitals, etc. 

$output = false; 

foreach ($stateArray as $abbreviation => $full) // Variable $stateArray is your list of Abbreviation => State Name pairs. 
{ 
    if ($userInput == $abbreviation || $userInput == $full) // Use (strtolower($userInput) == strtolower($abbreviation) || strtolower($userInput) == strtolower($full)) to change all the comparison values to lowercase. 
    // This is one example of processing the strings in a way to ensure some flexibility in the user input. 
    // However, whatever processing you need to do is determined by your needs. 
    { 
     $output = array($abbreviation => $full); // If you want a key => value pair, use this. 
     $output = $abbreviation; // If you only want the key, use this instead. 
     break; 
    } 
} 

if ($output === false) 
{ 
    $output = array("ZZ" => "OTHER"); // If you want a key => value pair, use this. 
    $output = "ZZ"; // If you only want the key, use this instead. 
} 

编辑：我已经改变了循环，这样它会检查用户输入对的缩写和完整的国家名称在一种情况下，而不是让他们分开。

Answer 2

请与各国和缩写的数组：检查输入

$array = array("new york" => "ny", "california" => "ca", "florida" => "fl", "illinois" => "il"); 

：

$input = "nY"; 
if(strlen($input) == 2) // it's an abbreviation 
{ 
    $input = strtolower($input); // turns "nY" into "ny" 
    $state = array_search($input, $array); 
    echo $state; // prints "new york" 
    echo ucwords($state); // prints "New York" 
} 

// ----------------------------------------------------// 

$input = "nEw YoRk"; 
if(strlen($input) > 2) // it's a full state name 
{ 
    $input = strtolower($input); // turns "nEw YoRk" into "new york" 
    $abbreviation = $array[$input]; 
    echo $abbreviation; // prints "ny"; 
    echo strtoupper($abbreviation); // prints "NY" 
} 

Answer 3

if (!isset($array[$input])) 
{ 
    // swap it 
    $temp = array_flip($array); 

    if (isset($temp[$input])) 
    { 
    echo 'Got it as abbreviation!'; 
    } 
    else 
    { 
    echo 'NO Match'; 
    } 
} 
else 
{ 
    echo 'Got it as state!'; 
} 

Answer 4

$array = array("New York" => "NY", 
"California" => "CA", 
"Florida" => "FL", 
"Illinois" => "IL"); 

$incoming = "New York"; 

if( in_array($incoming, $array) || array_key_exists($incoming, $array)){ 

echo "$incoming is valid"; 

}