PHP/HTML Add onclick function to subcategories with certain name

I am trying to add an onclick function for only certain recursively generated subcategories.

This code currently displays the subcategories correctly:

                    <?php if($parent) { ?>
                      <?php $search_params['sCategory'] = $parent['pk_i_id']; ?>
                      <a href="<?php echo osc_search_url($search_params); ?>" class="parent active" data-name="sCategory" data-val="<?php echo $parent['pk_i_id']; ?>">
                        <span class="name"><?php echo $parent['s_name']; ?></span><em>(<?php echo ($parent['i_num_items'] == '' ? 0 : $parent['i_num_items']); ?>)</em>
                      </a>
                    <?php } ?>
                    <?php foreach($categories as $c) { ?>
                      <?php $search_params['sCategory'] = $c['pk_i_id']; ?>

                      <a href="<?php echo osc_search_url($search_params); ?>" class="child<?php if($c['pk_i_id'] == $search_cat_id) { ?> active<?php } ?>" data-name="sCategory" data-val="<?php echo $c['pk_i_id']; $
                        <span class="name"><?php echo $c['s_name'];?></span><em>(<?php echo ($c['i_num_items'] == '' ? 0 : $c['i_num_items']); ?>)</em>
                      </a>

                    <?php } ?>
                  </div>

I would like to call say functionX(); written in JS for only the subcategory named "catx".

FunctionX() is working correctly when called else where.

I've tried something like this but get a White screen:

    <?php if($search_params == "catX") {
    echo '<a onclick="functionX();" href="<?php echo osc_search_url($search_params); ?>" class="parent active" data-name="sCategory" data-val="<?php echo $parent['pk_i_id']; ?>">
      <span class="name"><?php echo $parent['s_name']; ?></span><em>(<?php echo ($parent['i_num_items'] == '' ? 0 : $parent['i_num_items']); ?>)</em>
    </a>;'
    } else {
    echo '<a href="<?php echo osc_search_url($search_params); ?>" class="parent active" data-name="sCategory" data-val="<?php echo $parent['pk_i_id']; ?>">
      <span class="name"><?php echo $parent['s_name']; ?></span><em>(<?php echo ($parent['i_num_items'] == '' ? 0 : $parent['i_num_items']); ?>)</em>
      </a>;' ?>

Pretty new to this, thanks for the help!