how to pass POST variable by links to own pages?
Hi i wannna get variable $_POST by link to self pages. Example :
开发者_Go百科<?PHP
$var = 'PIG';
echo "<a href='test.php?var=$var'>link</a>";
if (isset($_POST['var']))
{
echo $_POST['var']);
}
?>
it links to own pages. (test.php) It not works, who can help me please. Thanks
A link cannot POST data, only GET.
In contrast to the GET request method where only a URL and headers are sent to the server, POST requests also include a message body. This allows for arbitrary length data of any type to be sent to the server.
Basically, a POST requires two requests, 1) the server receives the "normal" request, with an extra header value indicating that more data needs to be sent. At that point, the server sends an acknowledge and 2) the client sends the POST body. This behavior cannot be achieved only with a link.
However, there are solutions to this and I have seen some technique, among others, outputting a form with an autosubmit, something like
<form name="frm" method="post" action="http://your.domain.com/path/to/page.php?param1=1¶m2=2">
<input type="hidden" name="foo" value="bar" />
</form>
<script type="text/javascript">
document.forms["frm"].submit();
</script>
which would result into calling page.php with these arguments
$_GET = array('param1' => '1', 'param2' => '2');
$_POST = array('foo' => 'bar');
Note that this is a simple "redirect" method, but you can create <a> elements to actually trigger some hidden form like that instead of using the standard link. (untested code)
<a href="http://your.domain.com/path/to/page.php?param1=1¶m2=2" onclick="return dopost(this.href, {foo:'bar'});">A simple link</a>
<script type="text/javascript">
function dopost(url, params) {
var pe = '';
for (var param : params) {
pe += '<input type="hidden" name="'+param+'" value="'+params[param]+'" />';
}
var frmName = "frm" + new Date().getTime();
var form = '<form name="'+frmName+'" method="post" action="'+url'">'+pe+'</form>';
var wrapper = document.createElement("div");
wrapper.innerHTML = form;
document.body.appendChild(wrapper);
document.forms[frmName].submit();
}
</script>
This is probably what you need, actually.
Items in the query string are available via $_GET, not $_POST, since they are not actually POSTed. If you want to POST then you must either use a form with a method of post, or you must perform a XHR as POST.
Unfortunately, you really can't do that. If you need to use an anchor to submit a value, then you will need to access the variables through $_GET or $_REQUEST.
If it has to be a $_POST (if you are set in that design decision, because $_GET actually makes a lot more sense there), you can use a form and the style the submit button to make it look very much like a link. Put this code in a text editor and check it out.
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html>
<head>
<style type="text/css">
.button {border:none;background-color:#FFFFFF}
.button:hover{ color:blue; }
</style>
</head>
<body>
<form action="test.php">
<input type="hidden" name="var" value="<?php echo $val; ?>" />
This kinda looks like a link:
<input type="submit" value="link" class="button" />
</form>
</body>
</html>
If you have multiple links and you don't want to rewrite all of them, just add one fake form like this:
<form id="fakeForm" method="post">
<input type="hidden" name="post_key" value="post_value" />
</form>
and set up proper jquery:
$('a').click(function(event){
event.preventDefault();
$('#fakeForm').attr('action',$(this).attr('href')).submit();
});
In this case, when you click on any link, the landing page receives the post_value variable.
Note that if the link is clicked with other than left click (or js is disabled), the link works properly, but the value isn't passed!
This code below demonstrates T30's idea works.
My rationale for passing via $_POST is to prevent certain variables from being exposed in the url which is accomplished here. However, they would still be exposed via "view source".
<?php
/*
This demonstrates how to set $_POST from a link in .php without ajax based on the idea from http://stackoverflow.com/a/27621672/1827488. The rationale for doing so is to prevent certain variables ('userid') from being exposed in the url via $_GET. However, there does not seem to be a way to avoid those variables being exposed by 'view source'.
*/
echo "<!DOCTYPE html><html lang='en'><head><title>Test Data Link</title></head><body>";
// only one hidden form
echo "<form class='hiddenForm' method='post'>
<input class='hiddenFormUserid' type='hidden' name='userid'/>
</form>";
// as many links as you need
echo "<p><a class='hiddenFormLink' href='?following=1' data-userid=101>Following</a> • <a class='hiddenFormLink' href='?followers=1' data-userid=101>Followers</a></p>";
echo "<p><a class='hiddenFormLink' href='?following=1' data-userid=102>Following</a> • <a class='hiddenFormLink' href='?followers=1' data-userid=102>Followers</a></p>";
echo "<p><a class='hiddenFormLink' href='?following=1' data-userid=103>Following</a> • <a class='hiddenFormLink' href='?followers=1' data-userid=103>Followers</a></p>";
echo "<script src='https://ajax.googleapis.com/ajax/libs/jquery/2.1.4/jquery.min.js'></script>";
echo "<script type='text/javascript'>
console.log('jq');
$('.hiddenFormLink').click(function(e){
console.log('data-userid=' + $(this).attr('data-userid') + ', value=' + $('.hiddenFormUserid').val());
e.preventDefault();
$('.hiddenFormUserid')
.val($(this).attr('data-userid'));
$('.hiddenForm')
.attr('action',$(this).attr('href'))
.submit();
});
</script>";
if (isset($_GET["following"]) || isset($_GET["followers"])) {
if (isset($_GET["following"])) {
echo "followed by ";
} else {
echo "followers of ";
}
if (isset($_POST["userid"])) {
echo $_POST["userid"]."<br>";
} else {
echo "no post<br>";
}
} else {
echo "no get<br>";
}
echo "</body></html>";
$_POST["userid"] = "";
?>
加载中,请稍侯......
精彩评论