PHP没有将变量传递给其他页面

Question

I'm trying to pass the variable from one page to another. However, when I try to get the variable using php it just passes it as a string to the other page.

'<a href="selected.php?varname=<?php echo $row[title]; ?>">' . $row['title'] . '</a>'

This is a cell in a table and is a link that when clicked should go the other page with the title. However, instead I get this.

array (size=1) 'varname' => string '' (length=26)

        <?php
        $mysqli = mysqli_connect('localhost','scott','tiger','courses');
        if(mysqli_connect_errno($mysqli)) {
            echo 'Failed to connect to MySQL: ' . mysqli_connect_error();
        }

        class Courses
        {
            public $title;
            public $id;
            public $award;
        }


        $res = mysqli_query($mysqli, "SELECT title,id,award FROM course LIMIT 10");
        echo "<table align='center' style='margin: 0px auto;'>";
        while($row = $res->fetch_assoc()) {
            $courses = new Courses;
            $courses->title = $row['title'];
            $courses->id = $row['id'];
            $courses->award = $row['award'];
            $varname = $row['title'];
            echo "<tr><td style='padding-right:25px'>" . '<a href="selected.php?varname=<?php echo $row[title]; ?>">' . $row['title'] . '</a>' . "</td><td style='padding-right:25px'>" . $row['id'] . "</td><td style='padding-right:25px'>" . $row['award'] . "</td></tr>";
        }
    ?>

That is the rest of the php code.

            <?php
            $var_value = $_GET['varname'];

            echo serialize($var_value);

            var_dump($_GET);
            exit;

This is where I try to get it in the other page

Answer 1

Rewrite the code as below

"<a href='selected.php?varname=$row[title]'>$row['title']</a>"

As said in the docs

The most important feature of double-quoted strings is the fact that variable names will be expanded