ssjs.guide SFMC

ContentBlockByKey

→ string

Renders a Content Builder asset by its customer key and returns the rendered HTML string.

Available in: Email CloudPage Automation Triggered Send

Syntax

ContentBlockByKey(customerKey)
1 argument

Parameters

Name Type Required Description
customerKey string Yes The customer key (external key) of the Content Builder asset.

Description

ContentBlockByKey() renders a Content Builder block and returns the processed HTML. It’s the SSJS equivalent of the AMPscript ContentBlockByKey() function (the global function works identically to Platform.Function.ContentBlockByKey()).

The returned string contains the fully rendered HTML, including any personalization variables resolved within the content block.

Examples

Render a content block

var headerHtml = ContentBlockByKey("header-navigation");
Write(headerHtml);

Conditional content block

var sk = Platform.Request.GetQueryStringParameter("sk");
var isVIP = Platform.Function.Lookup("Subscribers", "IsVIP", "SubscriberKey", sk);

var blockKey = (isVIP === "1") ? "vip-welcome-block" : "standard-welcome-block";
Write(ContentBlockByKey(blockKey));

Composing a page from blocks

Write(ContentBlockByKey("page-header"));
Write('<main class="content">');
Write(ContentBlockByKey("main-content-" + pageId));
Write('</main>');
Write(ContentBlockByKey("page-footer"));

Notes

  • The customer key is set in Content Builder under the asset’s properties
  • The content block is processed server-side, so any AMPscript or SSJS inside it also executes
  • Returns an empty string if the block is not found (no error thrown)
  • Use ContentBlockByName() if you don’t have the customer key

See Also

See Also