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<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>字符串拼接方式</title>
<script type="text/javascript">
//方法一:普通拼接
var begindate = new date();
var str = "";
for (var i = 0; i < 100000; i++) {
str += "text";
}
var enddate = new date();
document.write("方法一:普通拼接,耗时:" + (enddate.gettime() - begindate.gettime()) + "毫秒<br/>");
//方法二:数组拼接
function stringbuilder() {
this.__strings__ = new array;
stringbuilder.prototype.append = function (str) {
this.__strings__.push(str);
stringbuilder.prototype.tostring = function () {
return this.__strings__.join("");
var begindate2 = new date();
var builder = new stringbuilder();
builder.append("text");
var result = builder.tostring();
var enddate2 = new date();
document.write("方法二:数组拼接,耗时:" + (enddate2.gettime() - begindate2.gettime()) + "毫秒<br/>");
</script>
</head>
<body>
</body>
</html>
《javascript高级程序设计》一书上说,直接拼接字符串会造成性能问题,应该采用array对象存储字符串,然后用join()方法创建最后的字符串。说可以节省50%~66%的时间,但是我测试发现,用数组拼接的方式往往还更耗时,如何解释呢?