How to display element characters in php arrays

How do I display the characters of an element in a php array? $ Data ['A'] = 1; $ data ['B'] = 2; $ data ['c'] = 3; I want to display: abc is not to display the element value, but to display the characters of the element itself. What are you talking about? $ Data = array ('a' = & gt; 1, 'B' = & gt about the php array, how do I display the characters of the element itself?
$ Data ['A'] = 1;
$ Data ['B'] = 2;
$ Data ['c'] = 3;

I want to display:
A
B
C

Not to display the element value, but to display the characters of the element itself

------ Solution --------------------
What are you talking about?

$ Data = array ('a' => 1, 'B' => 2, 'C' => 3 );

Foreach ($ data as $ key => $ value ){
Echo $ key;
}
Key? What do you mean.