Undefined variable (opencart)
问题 on the line where the error apparently is the code looks like this: <?php if ($filter_name) { ?> I know this is probably a vague questions but if anyone can help that would be great! 回答1: This is very Vague question. most probably you would be getting this error in header.tpl because you are using theme made for 1.5.4.x ( or earlier) with 1.5.5.x in your catalog/view/theme/your_theme/template/common/header.tpl Find <?php if ($filter_name) { ?> <input type="text" name="filter_name" value="<