Hello!
Thank you for your inquiry.
I’m Viktor, the developer on Aspose.Words Team responsible for integration with Aspose.Pdf. My colleagues asked me to take a look at this thread.
As I see from the discussion you are going to substitute strings like '[ck]' with real check marks. Check mark can be represented by character with code 0xF054 (hexadecimal) of Wingdings 2 font. This is the way how we simulate check marks when exporting to PDF. So substitution should be considered in two steps: replacing text and changing font. First task wouldn’t be a problem alone. But for the second you also need to split runs in a paragraph at the boundaries of substitution. For instance, you have a paragraph with homogenous formatting:
Select this check mark [ck] to enable caching.
Most probably it consists of only one run. But you will clone it producing three runs, modify text and change font in the middle run. Then insert clones to the paragraph in proper order.
There could be considered easier way. You can perform ordinary replacement. After it newly placed text will be put in separate runs and you can just change their font. But character 0xF054 can accidentally occur in the document and will be involved in the process. I would prefer more reliable solution.
Please let me know if this helps.
Regards,
Viktor Sazhaev
Software Engineer,
Aspose Auckland Team