
<!DOCTYPE html>
<html>
<body>
<p>假设 y=5,计算 x=y+2,并显示结果。</p>
<button onclick="Suan()">计算</button>
<p id="jieguo"></p>
<script>
function Suan(){
var y=5,x=y+2;
document.getElementById('jieguo').innerHTML="x="+x;
}
</script>
</body>
</html>


