tinymce-docs-4x/_includes/configuration/urlconverter-callback.md

urlconverter_callback

This option enables you to add your own URL converter logic. This option should contain a JavaScript function name.

The format of the converter function is: URLConverter(url, node, on_save), where:

• url = the URL string to convert,
• node = the element that contains the URL that is to be converted (this parameter may be set to null if there is no element for the URL), and
• on_save is always set to true.
• name = the attribute name that is being set.

This function should return the converted URL as a string. This option is set to an internal TinyMCE function .convertURL() by default. You may call this function from your extension in order to use the built-in convert options.

Type: Javascript Function

Example:

function myCustomURLConverter(url, node, on_save, name) {
  // Do some custom URL conversion
  url = url.substring(3);

  // Return new URL
  return url;
}

tinyMCE.init({
  selector: "textarea",  // change this value according to your html
  urlconverter_callback : "myCustomURLConverter"
});