http_build_query没有给出有效的字符串

    $requestParams = [ 'aame_uuid' => 'aba627', 'currency' => 'TEST'];

   ksort($requestParams);

   $hashString = http_build_query($requestParams);

    var_dump( $hashString); 

gives

string(30) "aame_uuid=aba627¤cy=TEST"

so why does currency transformed to ¤cy , how can correct it ?

I think the problem is the &curren html code. http://character-code.com/currency-html-codes.php &curren gets replaced to this char.

Maybe you should add an specific seperator like & to the http_build_query to make sure it will replaced to foo.php?aaaa_uid=aba627&currency=Test

I just tested your code and I get the following string back:

C:\wamp64\www\test\test.php:8:string 'aame_uuid=aba627&currency=TEST' (length=30)

It seems to be working fine for me. Have you tried using some other key? If it gives somewhat the same result your file or server could be corrupt.

If not the word curren might be presaved as a function to do something (which is highly unlikely). Did you mistype it as currentcy maybe (current is a php function)?