If I understand your scenario correctly, you wish your users to insert placeholders
with the help of RadEditor and these placeholders will be replaced with some database content on the server.
Perhaps the easiest way to tackle this task would be to use *system* strings that have some fixed starting and ending characters, e.g. ##FirstName##, or @@FirstName@@ - or something similar. Of course you can highlight these strings with HTML tags and inline styles, e.g.
<span style="background-color: #ffc000;border: 1px solid red;">##FirstName##</span>
You should instruct your users what the list of those *system*strings is, so that they can insert those where needed. Then, on the server side, all you need to do is run some simple String.Replace methods that will replace such a string with the exact database row data.
Note that it is not possible to have only an opening or only a closing tags in the content area, because the browser works with DOM nodes and each node should have an opening and a closing tag, and if some of both is missing the browser will add it automatically.
the Telerik team
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