For a survey, the best way to do this is to do it at the start of the survey, and collect their consent as part of a form. This means you will not have a printed consent form, but you will have consent. This is pretty much standard practice in much of the world for surveys that require consent these days. for more information on how to do this I suggest joining the Association of Internet Researcher's mailing list or asking their ethics committee for help

Hi, I completely agree with Jeremy Hunsinger in terms that the consent form will be at the very beginning of the survey and responders will have the option to accept/reject to participate in the study by giving their consent. In terms of getting IRB approval, this will not be different from a printed version of your informed consent and questionnaire. Take into account that the issues may be other such as the security of the data and the choice of a platform that satisfies minimal ethical standards. The best way would be to ask directly to the IRB that is going to review your study to assure that you understand how they are going to review your study.