php 丢失时为 URL 添加 http:// 前缀
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Add http:// prefix to URL when missing
提问by DiegoP.
Hello I have a very simple code
你好我有一个非常简单的代码
<a href="'.$aProfileInfo['Website'].'" target="_self">
<div class="callButton">Website</div>
</a>
The problem is that if the user does not enter http:// the link will then point to my website and not to the external website as it should.
问题是，如果用户没有输入 http:// 链接将指向我的网站，而不是它应该指向的外部网站。
How do I check in PHP if the user has not entered http:// and automatically add it when it is not there?
如果用户没有输入 http:// 并在它不存在时自动添加它，我如何检查 PHP？
采纳答案by Christopher Armstrong
A simple solution which may not work in all cases (i.e. 'https://'):
一个可能不适用于所有情况的简单解决方案（即“https://”）：
if (strpos($aProfileInfo['Website'],'http://') === false){
$aProfileInfo['Website'] = 'http://'.$aProfileInfo['Website'];
}
回答by David
I think you'd better use the built in function parse_url()which returns an associative array with its components
我认为你最好使用内置函数parse_url()，它返回一个关联数组及其组件
something like this will work for you:
这样的事情对你有用：
if ( $ret = parse_url($url) ) {
if ( !isset($ret["scheme"]) )
{
$url = "http://{$url}";
}
}
回答by Satbir Kira
I personally use this, which is partially taken from php docs
我个人使用这个，它部分取自 php docs
$scheme = parse_url($link, PHP_URL_SCHEME);
if (empty($scheme)) {
$link = 'http://' . ltrim($link, '/');
}
回答by Evan Kennedy
There are two ways of tackling this problem: url parsing and regular expressions.
有两种方法可以解决这个问题：url 解析和正则表达式。
Some will say url parsing is right, but regular expressions work just as well in this case. I like being able to have simple one-liners for things like this especially because this would be a common occurrence in template files where you may need a one-liner inside an echo statement to maintain readability.
有些人会说 url 解析是正确的，但正则表达式在这种情况下也能正常工作。我喜欢能够为这样的事情使用简单的单行，特别是因为这在模板文件中很常见，在这种情况下，您可能需要在 echo 语句中使用单行来保持可读性。
Regular Expressions
常用表达
We can do this in a single function call with preg_replace.
我们可以使用preg_replace在单个函数调用中完成此操作。
preg_replace('/^(?!https?:\/\/)/', 'http://', $aProfileInfo['Website'])
This uses a negative lookaheadat the beginning of the string that looks for http://or https://. If either are found, the replace doesn't happen. If they aren'tfound, it replaces the beginning of the string (0 characters) with http://essentially prepending this to the string without modifying it.
这negative lookahead在查找http://or的字符串开头使用 a https://。如果找到其中之一，则不会发生替换。如果他们没有找到，它会替换字符串（0字符）与年初http://基本前面加上这个字符串，而无需修改它。
In context:
在上下文中：
<a href="'. preg_replace('/^(?!https?:\/\/)/', 'http://', $aProfileInfo['Website']).'" target="_self">
<div class="callButton">Website</div>
</a>
URL Parsing
网址解析
(parse_url($aProfileInfo['Website'], PHP_URL_SCHEME) ? '' : 'http://') . $aProfileInfo['Website']
What this does is find out if a scheme is present on the link throught parse_url($aProfileInfo['Website'], PHP_URL_SCHEME). Then using a ternary operator, it will either output ''if there was one found or 'http://'if one wasn't found. Then it appends the link onto that.
这样做的目的是通过 找出链接上是否存在方案parse_url($aProfileInfo['Website'], PHP_URL_SCHEME)。然后使用三元运算符，''如果找到或未找到，它将输出'http://'。然后它将链接附加到该链接上。
In context:
在上下文中：
<a href="'.((parse_url($aProfileInfo['Website'], PHP_URL_SCHEME) ? '' : 'http://') . $aProfileInfo['Website']).'" target="_self">
<div class="callButton">Website</div>
</a>
回答by kevinji
回答by Hailwood
You can use this function as a general if nothing from the array is found in the stringappend something to it.
如果在字符串中未找到数组中的任何内容，则可以将此函数用作一般函数。
function httpify($link, $append = 'http://', $allowed = array('http://', 'https://')){
$found = false;
foreach($allowed as $protocol)
if(strpos($link, $protocol) !== 0)
$found = true;
if($found)
return $link;
return $append.$link;
}
回答by ggonzal
You also may take into account that "http(s)" must be at the beginning of the url:
您还可以考虑到“http(s)”必须位于 url 的开头：
if (preg_match('/^https?:\/\//', $aProfileInfo['Website']) === 0) {
$aProfileInfo['Website'] = 'http://'.$aProfileInfo['Website'];
}
回答by Porta Shqipe
Here is another example with string subtraction:
这是字符串减法的另一个示例：
$changeLink = $myRow->site_url;
if(substr($changeLink, 0, 7) != 'http://') {
$changeLink = 'http://' . $changeLink;
}
// ....
// ....
echo "<a href=\"" . $changeLink . "\" target=\"_blank\"></a>";
回答by Nate
I believe David's answeris the proper way to do this, but it can be simplified like this:
我相信大卫的回答是正确的方法，但可以像这样简化：
parse_url($aProfileInfo['Website'], PHP_URL_SCHEME)==''?'http://'.$aProfileInfo['Website']:$aProfileInfo['Website']
回答by gpresland
Something like this?
像这样的东西？
if (!strpos($aProfileInfo['Website'], 'http://')) {
$aProfileInfo['Website'] = 'http://' . $aProfileInfo['Website'];
}
