excerpt only when text is longer than defined excerpt length

[3muchfun]

Dear all,
I would like to add the condition to the following code, that the read more button shall not show up, when the text is shorter than the defined excerpt length. Any idea?

<div class="post-content">

    {{#if hasCustomExcerpt}}
        {{{excerpt}}}
    {{else}}
        {{{excerpt}}} {{/if}}
</div>

{{#if @config.custom.ReadMore}}
    <p>
        <a href="{{url}}" class="more-link">Continue reading</a>
    </p>
{{/if}}