Content Blocks is a property-editor used for creating a list of structured content, with each block configurable using an element type.
If you are using Umbraco 8.7 (or above), this may sound familiar to the Block List Editor, and you may be questioning why you should use Content Blocks over the built-in Block List Editor? It's a good question, but you'll find no comparisons or marketing spin from me, I'd recommend that you stick with Umbraco's built-in editors. Content Blocks has subtle differences, it's entirely your choice.
For long time fans of Umbraco v7.x, if you recall the Stacked Content editor, then Content Blocks could be considered its spiritual successor.
Select the data type, here are the options
Display mode - Stack or List (extensible)
Block types - configure element types - element type - name template - overlay size - enable preview
Enable filter - in overlay
Max items
Disable sorting
Enable dev mode
Press the Add button
Select block from overlay
Edit in panel.
Options - copy block; create content template
Razor views, found within the /Views/Partials/Blocks/ folder
Mention the view-model + view-data properties (icon, index/position)
NOTE: Preview doesn't work on a new unsaved page. As it has no page context.
IEnumerable<IPublishedElement>If using ModelsBuilder, it'll be castable to the desired element type model.
Alternative block editor options (for Umbraco v8) Perplex Content Blocks Bento editor