在大多数较新的浏览器中，你有 .toISOString（）方法，但在IE8或更老版本中你可以使用以下内容（取自Douglas Crockford的 json2.js ）：

In most newer browsers you have .toISOString() method, but in IE8 or older you can use the following (taken from json2.js by Douglas Crockford):

// Override only if native toISOString is not defined
if (!Date.prototype.toISOString) {
    // Here we rely on JSON serialization for dates because it matches 
    // the ISO standard. However, we check if JSON serializer is present 
    // on a page and define our own .toJSON method only if necessary
    if (!Date.prototype.toJSON) {
        Date.prototype.toJSON = function (key) {
            function f(n) {
                // Format integers to have at least two digits.
                return n < 10 ? '0' + n : n;
            }

            return this.getUTCFullYear()   + '-' +
                f(this.getUTCMonth() + 1) + '-' +
                f(this.getUTCDate())      + 'T' +
                f(this.getUTCHours())     + ':' +
                f(this.getUTCMinutes())   + ':' +
                f(this.getUTCSeconds())   + 'Z';
        };
    }

    Date.prototype.toISOString = Date.prototype.toJSON;
}

现在你可以安全地调用`.toISOString（）方法。

Now you can safely call `.toISOString() method.