How to get value of an associative HTML array in PHP using a string?

Question

Look I have a form like this:

I want t

Answer 1

It's hard to believe that this is a requirement. If you could expand more on what you're trying to achieve, someone undoubtedly has a better solution. However, I will ignore the eval = evil haters.

To echo:

eval("echo \$_POST$str;");

To assign to a variable:

eval("\$result = \$_POST$str;");

If you're open to another syntax then check How to write getter/setter to access multi-level array by key names?