currentElementNo = 0;
function nextElement( keyCode ) {
if (keyCode == 13) {
currentElementNo++;
currentElementNo %= document.formA.elements.length;
if ( document.formA.elements[currentElementNo].type != 'button') {
document.formA.elements[currentElementNo].focus();
} else {
currentElementNo++;
}
}
}

HTML部
'<'body onkeydown="nextElement(event.keyCode); return true;">

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