代码示例:(标识:eg_js_string_indexof_2)
<!DOCTYPE html>
<html>
<body>

<h1>JavaScript 字符串方法</h1>

<p>indexOf() 方法接受第二个参数作为搜索的起始位置:</p>

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

<script>
var str = "The full name of China is the People's Republic of China.";
var pos = str.indexOf("China",18);
document.getElementById("demo").innerHTML = pos;
</script>

</body>
</html>
运行结果: