是否可以使用href ='javascript：history.go（-1）通过“返回”按钮发送变量

Question

I'm using the following code and would like to send a variable back to the previous page when clicked:

echo "<center> Photo #{$Count} | <a href='javascript:history.go(-1)'>Go Back</a></center>"

I thought I could do something like this but it doesn't work: I added ?VP='Y'

echo "<center> Photo #{$Count} | <a href='javascript:history.go(-1)'?VP='Y'>Go Back</a></center>"

Answer 1

Since you tagged PHP, you could do

echo "<center> Photo #{$Count} | <a href='".$_SERVER['HTTP_REFERER']."?VP=Y'>Go Back</a></center>";

Then on the other page

$var = $_GET['VP'];

Answer 2

Would this work?

<a href='' id="back">Go Back</a>
<script>
document.getElementById("back").href = document.referrer + "?variable=value";
</script>

Note that document.referrer will be empty if the user navigated to the page directly. Of course thats a problem, why maybe this would be a back up solution:

<a href='' id="back">Go Back</a>

<script>
var ref = document.referrer;

if(ref == "") {
    ref = "javascript:history.go(-1);";
} else {
    ref = ref + "?variable=value";
}

document.getElementById("back").href = ref;
 </script>

Answer 3

I see you are using php, so you could solve it by making a simple form with the $_SERVER['HTTP_REFERER'] as the action and add a hidden field with the value. Or add a session variable :) SESSION['yourvar'] = 'whatever'

Then on the next page you get it using the $_GET or $_POST from the form or get the session variable by echo $_SESSION['yourvar'] . When working with sessions make sure you start them at the start of your pages. More details here http://php.net/manual/en/book.session.php