Shorten multiple "if" statement to "for"

How do I shorten this into a “for” statement?

onClipEvent (enterFrame) {
var bttn = “0”;
if (_level0.bttn == “1”) {
_level0.mask2._y = _level0.btn1._y;
}
else if (_level0.bttn == “2”) {
_level0.mask2._y = _level0.btn2._y;
}
else if (_level0.bttn == “3”) {
_level0.mask2._y = _level0.btn3._y;
}
else if (_level0.bttn == “4”) {
_level0.mask2._y = _level0.btn4._y;
}
else if (_level0.bttn == “5”) {
_level0.mask2._y = _level0.btn5._y;
}
else if (_level0.bttn == “6”) {
_level0.mask2._y = _level0.btn6._y;
}
else if (_level0.bttn == “7”) {
_level0.mask2._y = _level0.btn7._y;
}
else if (_level0.bttn == “8”) {
_level0.mask2._y = _level0.btn8._y;
}
};

Something like this, but I know I’m way the flip off!!

onClipEvent (enterFrame) {
for (var i=0; i<=8; i++) {
if (_level0.bttn == “i”) {
_level0.mask2._y = _level0.“btn+i”._y;
}
}
};

Cheers,
jj

onClipEvent (enterFrame) {
for (var i=0; i<=8; i++) {
if (_level0.bttn == i) {
_level0.mask2._y = _level0[“btn”+i]._y;
}
}
};

You caught my error.

¡Gracias!
jj