Answers.Body: <p><code>craft.entries()</code> returns an <code>EntryQuery</code>. You must then <a href="https://craftcms.com/docs/3.x/element-queries.html#executing-element-queries" rel="nofollow noreferrer">execute the query</a> with one of those methods:</p>
  <ul>
  <li><code>one()</code></li>
  <li><code>all()</code></li>
  <li><code>count()</code></li>
  <li><code>exists()</code></li>
  </ul>
  <p>In your case, I think <code>.exists()</code> is the best choice: <code>{% if categoryListings.exists() %}</code></p>
  <p>Edit: You may also have to execute your category query with <code>{% for category in craft.categories().group('catGroup1').all() %}</code>. See <a href="https://craftcms.com/docs/3.x/categories.html#querying-categories" rel="nofollow noreferrer">https://craftcms.com/docs/3.x/categories.html#querying-categories</a>.</p>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2020-09-11T20:16:29.977Z
Answers.Text: i tried your answers and hints, but no luck. maybe my approach with the craft.entries() is not the right one.
Answers.UserDisplayName: Henrik
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2020-09-11T13:42:17.907Z
Answers.LastActivityDate: 2020-09-11T14:01:27.040Z
Answers.LastEditDate: 2020-09-11T14:01:27.040Z
Answers.UserDisplayName: nstCactus
Body: <p>I have entries, which can have several categories.
  These categories are in different categorie groups.</p>
  <p>Now if i show an entry page, i want to display i certain html block
  based on a specific category, the entry has or not.</p>
  <p>i tried this, but its not working, i think i get the relatedTo thing wrong:</p>
  <pre><code>//i loop through all the categories in my group
  
  {% for category in craft.categories.group('catGroup1') %}
  
  //the i go to the section my entries are in and relate that to the categories i want to filter
  
  {% set categoryListings = craft.entries({
    section: 'kelims',
    relatedTo: [
      { targetElement: category, field: 'filterThisCategory' }
    ]
  }) %}
  
  //if the entry has this category
  
  {% if categoryListings|length %}
  
    display some html block
  
  {% endif %}
  {% endfor %}
  </code></pre>
  
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2020-09-14T16:58:09.183Z
Comments.Text: I'm not sure I understand how you set the entry type in the `kelims` section. Could you tell me more about your `filterThisCategory` field? A screenshot of the field settings would help. 
  I'm also unsure I understood correctly what you try to achieve. You just want to output some HTML if the entry you're currently viewing has a specific category, right?
Comments.UserDisplayName: nstCactus
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2020-09-19T20:30:52.460Z
Comments.Text: My approach above was a wrong one. Regarding your last question, @nstCactus, yes, thats what i mean.
  I eventually fount the solution, with the help of these pages:
  https://craftcms.com/docs/3.x/categories-fields.html#templating,
  https://craftcms.com/docs/3.x/categories.html#querying-categories
  
  {% if entry.myFieldHandle.id('48, 49, 50, 51').exists() %}
   do this 
  {% else %}
   do this
  {% endif %}
  
  myFieldHandle is the fieldHandle of the Category Group, where the categories i am searching for, are in.
Comments.UserDisplayName: Henrik
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2020-09-19T20:35:56.793Z
Comments.Text: @nstCactus, so your hint with the "exists()" was the right one, but i needed to add the ids.
Comments.UserDisplayName: Henrik
Tags: <filter><conditional><relatedto>
Title: if entry has specific category, show specific html block
ThreadText: # if entry has specific category, show specific html block
  
  (Asked by: username_0 on 2020-09-11)
  
  I have entries, which can have several categories.
  These categories are in different categorie groups.
  
  Now if i show an entry page, i want to display i certain html block
  based on a specific category, the entry has or not.
  
  i tried this, but its not working, i think i get the relatedTo thing wrong:
  
  ```
  //i loop through all the categories in my group
  
  {% for category in craft.categories.group('catGroup1') %}
  
  //the i go to the section my entries are in and relate that to the categories i want to filter
  
  {% set categoryListings = craft.entries({
    section: 'kelims',
    relatedTo: [
      { targetElement: category, field: 'filterThisCategory' }
    ]
  }) %}
  
  //if the entry has this category
  
  {% if categoryListings|length %}
  
    display some html block
  
  {% endif %}
  {% endfor %}
  
  ```
  
  **Tags:** filter, conditional, relatedto
  
  > **Comments:**
  > **username_1**: I'm not sure I understand how you set the entry type in the `kelims` section. Could you tell me more about your `filterThisCategory` field? A screenshot of the field settings would help.  I'm also unsure I understood correctly what you try to achieve. You just want to output some HTML if the entry you're currently viewing has a specific category, right?  
  > **username_0**: My approach above was a wrong one. Regarding your last question, @username_1, yes, thats what i mean. I eventually fount the solution, with the help of these pages: https://craftcms.com/docs/3.x/categories-fields.html#templating, https://craftcms.com/docs/3.x/categories.html#querying-categories  {% if entry.myFieldHandle.id('48, 49, 50, 51').exists() %}  do this  {% else %}  do this {% endif %}  myFieldHandle is the fieldHandle of the Category Group, where the categories i am searching for, are in.  
  > **username_0**: @username_1, so your hint with the "exists()" was the right one, but i needed to add the ids.  
  
  ---
  
  ## 1 answers
  
  ### Answer by username_1 on 2020-09-11. Score: 1
  
  `craft.entries()` returns an `EntryQuery`. You must then [execute the query](https://craftcms.com/docs/3.x/element-queries.html#executing-element-queries) with one of those methods:
  
  * `one()`
  * `all()`
  * `count()`
  * `exists()`
  
  In your case, I think `.exists()` is the best choice: `{% if categoryListings.exists() %}`
  
  Edit: You may also have to execute your category query with `{% for category in craft.categories().group('catGroup1').all() %}`. See <https://craftcms.com/docs/3.x/categories.html#querying-categories>.
  
  > **Comments:**
  > **username_0**: i tried your answers and hints, but no luck. maybe my approach with the craft.entries() is not the right one.  
  
  ---
  
  