Array map use variable to identify column to return

Question

I am trying to use array map dynamically, the column in the array may change so I don't want to specify it using string but want to use a variable to specify it, it does not work. Tried all the following combinations, it returns null.

$column = 'MANAGER_GROUP';
array_map(function($el){ return $el['"'.$column.'"']; }, $dbData);
array_map(function($el){ return $el["$column"]; }, $dbData);
array_map(function($el){ return $el[$column]; }, $dbData);

//this works though
array_map(function($el){ return $el["MANGER_GROUP"]; }, $dbData);

You have to use the keyword "use" in php To access variables outside your Closure function which in your case the Callback Function.. see the answer Below by Tadas — Emz, Sep 21 '16 at 08:17

score 6 · Accepted Answer · answered Sep 21 '16 at 07:59

Anonymous function has it's own scope, it does not have access to parent scope automatically. You have to explicitly specify a variable to be passed to anonymous function context.

$column = 'MANAGER_GROUP';
array_map(function($el) use ($column) { 
    return $el[$column];
}, $dbData);

Array map use variable to identify column to return

1 Answers1