Javascript：document.referrer
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Javascript: document.referrer
提问by jagrti
Say I have included document.referrer()in my website(www.abc.com) and I got redirected to my site from google.com.
假设我已包含document.referrer()在我的网站 ( www.abc.com) 中，并且我从google.com.
Will the above mentioned code help me to get google.com?
上面提到的代码会帮助我得到google.com吗？
回答by Shadow Wizard is Ear For You
The search results in Google are not direct links. For example searching for abcthe first result actual link is:
http://www.google.co.uk/url?sa=t&source=web&cd=1&ved=0CC0QFjAA&url=http%3A%2F%2Fabc.go.com%2F&ei=_0nCTeOMFYOVswbY7PyHAQ&usg=AFQjCNHN69w2aXwjgMlF4X6o9W3lKd4uZw
Google 中的搜索结果不是直接链接。例如搜索abc第一个结果的实际链接是：
http://www.google.co.uk/url?sa=t&source=web&cd=1&ved=0CC0QFjAA&url=http%3A%2F%2Fabc.go.com%2F&ei=_0nCTeOMFYOVswbY7PyHAQ&usg=AFQjCNHN69w2aXwjgMlF4X6o9W3lKd4uZw
The redirection is then made server side so the code in abc.go.comwebsite might not get proper referrer.
然后重定向在服务器端进行，因此abc.go.com网站中的代码可能无法获得正确的引用。
回答by Konrad Borowski
javascript:alert(document.referrer);
When you will insert it at address bar, the previous location will appear, like the addresses appear on address bar, like http://php.net/manual/en/control-structures.break.php. You can use it to make complex JavaScript operations, like regular expressions. I will give very simple example
当您将其插入地址栏时，会出现之前的位置，就像地址栏上出现的地址一样，例如http://php.net/manual/en/control-structures.break.php。您可以使用它来进行复杂的 JavaScript 操作，例如正则表达式。我将举一个非常简单的例子
<script type="text/javascript">
if (document.referrer.search('google')==-1){
alert('Not using Google');
} else {
alert('Yes, from Google');
}
</script>
