<!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>