代码示例:(标识:eg_js_operator_concatenate_5)
<!DOCTYPE html>
<html>
<body>

<h1>JavaScript 运算符</h1>

<p>+ 运算符级联(相加)字符串。</p>

<p id="demo"></p>

<script>
var txt1 = "What a very";
var txt2 = "nice day";
document.getElementById("demo").innerHTML = txt1 + " " + txt2;
</script>

</body>
</html>
运行结果: