Sign using text string instead of digital signature

Good day,

I want to put a text from inputBox instead of digital signature, how do I do that in iOS Objective ?

If you are asking how to use text as the appearance of a Digital Signature, then you would use the ElementBuilder API to create the custom appearance.

For ElementBuilder API, you would be writing directly to the new content stream. You would start with this code (which shows how to add text also)
https://groups.google.com/d/msg/pdfnet-sdk/VKV_M2r8c_8/ELadsgU3R9gJ

And then using the code from our ElementBuilder sample add text.
https://www.pdftron.com/pdfnet/samplecode/ElementBuilderTest.m.html

If this is not what you are asking, please clarify. A screen shot would help also.