Question

I’d like to take an array with this structure:

array
  'Alabama' => 
    array
      0 => 
        array
          'id' => string '11' (length=2)
          'region_name' => string 'Alabama' (length=7)
          'city' => string 'Birmingham' (length=10)
      1 => 
        array
          'id' => string '12' (length=2)
          'region_name' => string 'Alabama' (length=7)
          'city' => string 'Huntsville' (length=10)
      2 => 
        array
          'id' => string '13' (length=2)
          'region_name' => string 'Alabama' (length=7)
          'city' => string 'Mobile' (length=6)
      3 => 
        array
          'id' => string '14' (length=2)
          'region_name' => string 'Alabama' (length=7)
          'city' => string 'Montgomery' (length=10)
  'Alaska' => 
    array
      0 => 
        array
          'id' => string '15' (length=2)
          'region_name' => string 'Alaska' (length=6)
          'city' => string 'Anchorage' (length=9)

And create unordered lists in html, like so:

<ul id="A">
    <li class="state">Alabama</li> 
    <li>Birmingham</li>
    <li>Huntsville</li>
    <li>Mobile</li>
    <li>Montgomery</li>
    <li class="state">Alaska</li>
    <li>Anchorage</li>
</ul> 
<ul id="C">
    <li class="state">California</li>
    <li>Bakersfield</li>
    <li>Fresno</li>
    <li>Los Angeles</li>
</ul>
<ul id="D">
    <li class="state">DC</li>
    <li>Washington</li>
</ul>

The idea is an alphabetically ordered and grouped series of unordered lists, which I can show and hide easily using javascript. That part is easy… This part, I’m lost.

I’ve tried a sort of nested foreach loop, but the framework I’m using refused to do it citing OutputEscaper errors, which I believe made sense – I really am not sure how to do this properly.

I’d appreciate any help!

edit: Here’s how the array is initially formatted:

$this->cityGroups = array();
foreach($this->USCities as $city)
{
  $this->cityGroups[$city['region_name']][] = $city;
}

Answer 1

This solution should achieve what you’re looking for:

$lastLetter = "A";
print( '<ul id="A">' );
foreach( $myArray as $key => $array ){
    if( strtoupper( substr( $key, 0, 1 ) ) != $lastLetter ){
        print( '</ul>' );
        $lastLetter = strtoupper( substr( $key, 0, 1 ) );
        print( '<ul id="' . $lastLetter . '">' );
    }
    print( '<li class="state">' . $key . '</li>' );
    foreach( $array as $subArr ){
        print( '<li>' . $subArr['city'] . '</li>' );
    }
}
print( '</ul>' );

If you need an explanation on any specific part, please let me know.

Alternate Solution, in the event your starting letter is variable (may or may not be A)

Change:

$lastLetter = "A";
print( '<ul id="A">' );

to:

$temp = array_keys( $myArray );
$lastLetter = strtoupper( substr( $temp[0], 0, 1 ) );
print( '<ul id="' . $lastLetter . '">' );