按钮上的php条件


php condition on button

我有这个问题:在下面的代码中,我制作了一个带有条件的表单,其中如果"profileid"在数组friends中,则打印按钮"add to friends",否则打印按钮"remove to friend斯",但第二个条件不起作用,则不打印任何内容。当我第一次加载页面时,如果数组中已经有"friend id",则会有按钮"add tofriends。

这是我的代码:

<?php
        $userid = $_SESSION['userid'];
        $profileid = $_SESSION['profileID'];
        $compressed_friends=mysql_query("SELECT friends FROM users WHERE id LIKE '$userid'");
        $friends = explode (',',$compressed_friends);
        if(isset($_POST['addFriends']))
        {
            $compressed_friends=$profileid.','.$compressed_friends;
            mysql_query("UPDATE users SET friends='$compressed_friends' WHERE id='$userid'");
        }
        elseif(isset($_POST['removeFriends']))
        {
            array_filter($friends,$profileid);
            $compressed_friends=implode(',', $friends);
            mysql_query("UPDATE users SET friends='$compressed_friends' WHERE id='$userid'");
        }
        else
        {
        ?>
        <form role="form" action="<?php echo $_SERVER['PHP_SELF']; ?>" method="POST">
        <?php
            if(!in_array($profileid, $friends))
            {
                echo' <button type="submit" name="addFriends" class="btn btn-primary col-lg-3">Add to friends</button>';
            }
            elseif(in_array($profileid, $friends))
            {
                echo '<button type="submit" name="removeFriends" class="btn btn-danger col-lg-3">Remove to Friends</button>';
            }
        ?>
        </form>
        <?php } ?>

让我试着回答,因为我是PHP初学者。我发现回声有问题。你曾经报道过"."

  echo' <button type="submit" name="addFriends" class="btn btn-primary col-lg-3">Add to friends</button>';

你可以试试这个,也许它能解决你的问题。

  echo  "<button type='submit' name='addFriends' class='btn btn-primary col-lg-3'>Add to friends</button>";

谢谢!