我正在阅读W3School的一些教程。此功能如何工作
我右键点击并查看网页源代码,发现在源代码中此功能:
function submitTryit() {
var t = document.getElementById("textareaCode").value;
t = t.replace(/=/gi, "w3equalsign");
var pos = t.search(/script/i)
while (pos > 0) {
t = t.substring(0, pos) + "w3" + t.substr(pos,3)
+ "w3" + t.substr(pos+3,3) + "tag" + t.substr(pos+6);
pos = t.search(/script/i);
}
document.getElementById("code").value = t;
document.getElementById("tryitform").action = "tryit_view.asp?x=" + Math.random();
validateForm();
document.getElementById("tryitform").submit();
}
function validateForm() {
var code = document.getElementById("code").value;
if (code.length > 5000) {
document.getElementById("code").value = "<h1>Error</h1>";
}
}
这是什么呢?
var pos = t.search(/script/i)
这是什么?
t = t.substring(0, pos) + "w3" + t.substr(pos,3)
+ "w3" + t.substr(pos+3,3) + "tag" + t.substr(pos+6);
我建议你搜索并查看官方文档*已经在网上*:[String.prototype.search()](https://developer.mozilla。org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/search)和[String.prototype.substring()](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/substring) –
你是在学习W3School的帮助下学习javascript,还是试图实现与W3School相同的功能?如果你只是在学习js,那么就没有必要查看w3school网站的源代码。 – rhgb