Replace any string or value in twig template variable.

If we want to Replace the value in twig template then we have an example and syntax, please have a look..
{#
    ****  replace '-' with '$' sign in vidyard ID ****  
#}

{% set twig_content_variable  = node.field_resources_vidyard_id.value  %}   // here we are applying on field_resources_vidyard_id field..
{% set replace_value_var      = '-' %}
{% set replace_with_value_var = '$' %}
{%if twig_content_variable %}
   {% set vidyard_function_id = twig_content_variable|replace({ '-': '$' }) %}
{% endif %}


Note: If have any suggestions or issue regarding 'Replace any string or value in twig template variable.' then you can ask by comments. 

Programmatically Media load in drupal 8.

If we want to load Media entity. we have to add library on the top of page. ( use Drupal\media\Entity\Media; )
Then its easy to load media entity by the syntax.
   
Syntax:
$media_detail = Media::load($mid);    // here $mid is media entity id       
   
now if we want to get image field data of media field then syntax is..

$media_img = file_create_url($media_detail->field_media_image->entity->getFileUri());
 // here field_media_image is field name in media entity
   
now if we want to get any text field value then syntax will be..

$media_caption = $media_detail->get('field_capt2120')->getValue();   
// here field_capt2120 is the machine name of caption field in media entity    

foreach($m_caption as $mkey){
   $capval = $mkey['value'];    // here we will get the caption value           
}


Note: If have any suggestions or issue regarding 'Programmatically Media load in drupal 8.' then you can ask by comments.   

Programmatically Node load and Multiple Node load in drupal 8.

In drupal 7, we have node_load($nodeid) for load the node but now in drupal 8 syntax is changed and now node load by Node::load($nodeid) or Add the name space at the top of the page. \Drupal\node\Entity\Node::load($nodeid);

If we are using Symfony library and calling name space

use Drupal\node\Entity\Node;

So we do not need to use node class in node::load, we just need the syntax like Node::load($nodeid);

but if we are not calling or render name space then for node load we need to use the syntax like

\Drupal\node\Entity\Node::load($nodeid);

For get the node detail fields by Node::load($nodeid) syntax is..

Example: This example is for single node load.

              $node_detail = Node::load($nodeid);

                                   OR

              $node_detail = \Drupal\node\Entity\Node::load($nodeid);

              $node_id = $node_detail->id();

              $node_title = $node_detail->getTitle();

              $node_status = $node_detail->isPublished();

              $node_type = $node_detail->type->target_id; 

              $node_field_select_id = $node_detail->get('field_machine_name')->target_id;

              $node_field_select_value = $node_detail->get('field_machine_name')->value;

--------------------------------------------------------------------------------------------------------------------------

In drupal 8 for load multiple nodes of any `Content Type`, we have Node::loadMultiple() and Drupal::entityQuery() functions for load all the nodes of given content type. We have an Example with Syntax for this, please have a look.
Syntax:
$all_nids = \Drupal::entityQuery('node')->condition('type','write content type machine name ')->execute();

Then pass the $get_all_nids variable to Node::loadMultiple function for get data..

$nodes = \Drupal\node\Entity\Node::loadMultiple($get_all_nids);

Example:
    $nids = \Drupal::entityQuery('node')->condition('type','applications')->execute(); // There application is my content type machine name..
    $node_detail = \Drupal\node\Entity\Node::loadMultiple($nids);
    foreach ($node_detail as $node){  // In node_detail array we have all nodes details..
        // here we are fetching fields detail.
        $title = $node->getTitle();
        $application_category_id = $node->field_application_category->target_id;       
        $img = file_create_url($node->field_application_image->entity->getFileUri());
        $image_gallery .='<div class ="imggallery"><img src="'.$img.'"><p>'.$title.'</p></div>';
    }
    // here returning $image_gallery array with image_gallery detail.
    return array(
    '#markup' => t($image_gallery),
    );       

   
Note: If have any suggestions or issue regarding 'Programmatically Node load and Multiple Node load in drupal 8. ' then you can ask by comments.   

How we can Url Alias in Drupal 8?

If you want to path alias in drupal 8 then we have different syntax in drupal 8, Please follow this.
Syntax:
$alias = \Drupal::service('path.alias_manager')->getAliasByPath($tid or $nid);

Example: like if we have taxonomy term and we want to path alias so first we create URL path as given exmaple..

$tid = '/taxonomy/term/'.$term_id;
$alias = \Drupal::service('path.alias_manager')->getAliasByPath($tid); or \Drupal::service('path.alias_manager')->getAliasByPath('/taxonomy/term/'.$term_id),

OR

$nid = '/node/'.$node_id;
$alias = \Drupal::service('path.alias_manager')->getAliasByPath($nid); or \Drupal::service('path.alias_manager')->getAliasByPath('/node/'.$node_id),


Simple then we can use this alias to send or redirect using
$response = new Symfony\Component\HttpFoundation\RedirectResponse($alias);
$response->send();
return; 


Note: If have any suggestions or issue regarding 'How we can Url Alias in Drupal 8?' then you can ask by comments.

How to render fields on node twig templates?

It is easy way to render node fields on node template. We just have to create template file according to content type machine name like 'landing page' is content type, So machine name will be 'landing_page', but our template name will be 'node--landing-pages--full.html.twig' as per Drupal 8(Symphony) Syntax.

and we will call/render fields like..


Node id: {{ node.id }} // Node id

Node Url: {{ url }}  // current page url

Node Title: {{ label }}  // Node title

Node Bundle: {{ node.bundle }}  // Node bundle its means content type name

Node Publish Status: {{ node.isPublished() }}  // Retrun node is published or not

Node Created Time: {{ node.getCreatedTime() }}  //will return node created timestamp

Node Plain(Text) Field: {{ node.field_machine_name.value }}  //will return node plain field value

Node Image: {{ file_url(node.field_full_banner_image.entity.fileuri) }} or {{ file_url(node.field_full_banner_image.entity.uri.value) }}  // show url of full banner image is the image field in node

Node Description/body: {{ content.body }}

Node Link field: {{ node.field_machine_name.0.url }}

Node Link Field Title Value: {{ node.field_machine_name.0.title }}

Node custom field: {{ content.field_machine_name }}  or {{ content.field_machine_name[0] }}  // ex:{{ content.field_resources_content_type }}

If you want to check field value return or not the we have multiple options like.
// here we are checking field banner video return or not.
{% if content.field_banner_video|render %}  
  // write comment here..
{% endif %}

OR

// here we are checking field carousel title is empty or not.
{% if content.field_carousel_title[0] is not empty %}
  // write comment here..
  {{ content.field_carousel_title[0] }}
{% endif %}


Split array in twig:

We have split option also in twig file in symphony, please have a look.
{% set videogal_value_variable = videogall|split('~~') %}
like 'videogall' is an array and separated by ~~ sign so we will do like this for break and use.
{{ videogal_value_variable.0 }}
{{ videogal_value_variable.1 }}
and so on.


Note: If have any suggestions or issue regarding 'How to render fields on node twig templates' then you can ask by comments.

drupal 8 images with custom style.

If we want to apply the custom styling on image path then we have to create first with go to Configuration -> media -> image styles or /admin/config/media/image-styles
then click on Add image style and according to requirement choose effect option like Convert, Crop, Resize, Rotate, Scale, Scale and Crop, Desaturate and apply height/width and save it, then get the machine name of your custom create style and apply like this syntax.

Image style listing

Add new image style

Apply Effect

Call the ImageStyle library on header of file.
use Drupal\image\Entity\ImageStyle;

Then get the uri of image..

$path = 'public://images/image.jpg';
$url = ImageStyle::load('style_machine_name')->buildUrl($path);   

OR direct use this syntax..
$product_image = \Drupal\image\Entity\ImageStyle::load('related_products')->buildUrl($nodeload->field_banner_image->entity->getFileUri());   

here 'related_products' is the machine name of custom image style and 'field_banner_image' is the machine name of banner image, and this is $nodeload->field_banner_image->entity->getFileUri() the uri of banner image by node::load.

Note: If have any suggestions or issue regarding 'drupal 8 images with custom style.' then you can ask by comments.

Vocabulary or Taxonomy load in Drupal 8.

If we have vocabulary/taxonomy name then we can easily load by loadTree, follow the syntax.

$tree = \Drupal::entityTypeManager()->getStorage('taxonomy_term')->loadTree('write vocabulary machine name here');
foreach ($tree as $term) {
  echo $term->tid.' - '.$term->name;
}

Example:
$select_category .= '<select><option value="0">- Select -</option>';
$tree = \Drupal::entityTypeManager()->getStorage('taxonomy_term')->loadTree('product_family'); //here product_family is machine name of Product Family taxonomy.
foreach ($tree as $term) {
$select_category .= '<option value="' . $parent . '_' . $term->tid . '">' . $term->name . '</option>';
}
$select_category .= '</select>';


Note: If have any suggestions or issue regarding 'Vocabulary or Taxonomy load in Drupal 8.' then you can ask by comments.