Javascript 检查推荐人
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Checking the referrer
提问by Ben Shelock
I'm using this to check if someone came from Reddit, however it doesn't work.
我用它来检查是否有人来自 Reddit，但它不起作用。
var ref = document.referrer;
if(ref.match("/http://(www.)?reddit.com(/)?(.*)?/gi"){
alert('You came from Reddit');
} else {
alert('No you didn\'t');
}
Suggestions on the regular expression are most welcome too.
也欢迎对正则表达式提出建议。
回答by gnarf
Try this:
尝试这个：
if (ref.match(/^https?:\/\/([^\/]+\.)?reddit\.com(\/|$)/i)) {
alert("Came from reddit");
}
The regexp:
正则表达式：
/^ # ensure start of string
http # match 'http'
s? # 's' if it exists is okay
:\/\/ # match '://'
([^\/]+\.)? # match any non '/' chars followed by a '.' (if they exist)
reddit\.com # match 'reddit.com'
(\/|$) # match '/' or the end of the string
/i # match case-insenitive
回答by Skilldrick
Close your ifparen...
关闭你的if家长...
回答by TimSmith-Aardwolf
I've been using an alternative to RegEx by looking for the domain in the referrer
我一直在通过在引用中查找域来使用 RegEx 的替代方法
if (document.referrer.indexOf('reddit.com') >= 0) { alert('They came from Reddit.com'); }
EDIT: As thekingoftruth points out that doesn't work if reddit.com is included in an URL parameter so I've extended it a little. I've also added toLowerCase() as I spotted that in the RegExp above.
编辑：正如 thekingoftruth 指出的那样，如果 reddit.com 包含在 URL 参数中是行不通的，所以我对其进行了一些扩展。我还添加了 toLowerCase()，因为我在上面的 RegExp 中发现了这一点。
if (document.referrer.indexOf('?') > 0){
if (document.referrer.substring(0,document.referrer.indexOf('?')).toLowerCase().indexOf('reddit.com') >= 0){
alert('They came from Reddit');
}
} else {
if (document.referrer.toLowerCase().indexOf('reddit.com') > 0){
alert('They came from Reddit');
}
}
回答by Gumbo
Try this:
尝试这个：
ref.match(new RegExp("^http://(www\.)?reddit\.com/", "i"))
Or:
或者：
ref.match(/^http:\/\/(www\.)?reddit\.com\//i)
回答by GeniusGeek
I would use this, wouldn't it be a lesser and simply way?
我会使用这个，这不是一种更简单的方法吗？
var referral= document.refferer;
If(referral.includes("www.reddit.com"){
alert("you came from reddit");
}
else{
alert("you didn't come from reddit");
{
回答by GeniusGeek
Use var ref = document.referer; // ONE R instead of TWO
使用 var ref = document.referer; // 一个 R 而不是两个
