src/PoHeader.php
public function getHeader(string $key): ?string
    {
        $this->buildStructuredHeaders();
        $lkey = strtolower($key);
        $header = null;
        if (isset($this->structuredHeaders[$lkey]['value'])) {
            $header = $this->structuredHeaders[$lkey]['value'];
        }
        return $header;
    }
public function getHeader(string $key): ?string
    {
        $this->buildStructuredHeaders();
        $lkey = strtolower($key);
        $header = null;
        if (isset($this->structuredHeaders[$lkey]['value'])) {
            $header = $this->structuredHeaders[$lkey]['value'];
        }
        return $header;
    }
public function getHeader ( string $ key ) : ? string { $ this -> buildStructuredHeaders ( ) ; $ lkey = strtolower ( $ key ) ; $ header = null ; if ( isset ( $ this -> structuredHeaders [ $ lkey ] [ 'value' ] ) ) { $ header = $ this -> structuredHeaders [ $ lkey ] [ 'value' ] ; } return $ header ; }
Get a header value string by key

@param string $key case insensitive name of header to return

@return string|null header string for key or false if not set
Get a header value string by key