JavaScript addField() Exception

[Gary W 0]

I tried to execute the following JavaScript codes in JavaScript Console but it returned an exception, saying that "RaiseError: Nitro internal error: => document.addField()". Could anyone provide help to point out what the exact issue is...? Please help.

this.addField("Text1","text", 3,[180,700,550,550]);

[Dods10 0]

try Doc.addField instead