如何用PHP生成这条HTML语句,并且可以运行?

Question

echo <<< EOF
<select size="1" name="GuestImageID" onchange="document.images.avatarpic.src ='images/'+this[this.selectedIndex].value;">
EOFecho '<select size="1" name="GuestImageID" onchange="document.images.avatarpic.src =\'images/\'+this[this.selectedIndex].value;">';

Answer 1

?><select size="1" name="GuestImageID" onchange="document.images.avatarpic.src ='images/'+this[this.selectedIndex].value;"><?

Answer 2

echo "<select size='1' name='GuestImageID' ".
 "onchange='document.images.avatarpic.src =images\/+this[this.selectedIndex].value;'>";