<!DOCTYPE html>
<html>
<body>
<h1>JavaScript 循环</h1>
<p id="demo"></p>
<script>
var text = "";
var i;
for (i = 0; i < 5; i++) {
text += "The number is " + i + "<br>";
}
document.getElementById("demo").innerHTML = text;
</script>
</body>
</html>
初学者，刚接触js，想知道为啥text += "The number is " + i + "<br>"; 这里要用+=，在for循环里不应该是text = "The number is " + i + "<br>";就可以循环吗
