Q:

How to print values from bibtex entry fields?

I have multiple website references on my document. I'm using bibtex with @misc to specify them.
I need to keep switching between referencing this sites in the normal way together with all the other references, or have them in footnotes. I want to make this switches as painless as possible and so my idea is to use a new command to cite a website, say \wcite. I would define it as:
\newcommand{\wcite}[1]{\cite{#1}} %normal cite  
\newcommand{\wcite}[1]{\footnote{\bibtitle{#1} - \bibhowpublished{#1}}} %footnote cite  

Then I would comment the one I'm not using at the moment. This allows me to switch from citations to footnotes quickly, writing the website's data only once. I can also easily change the format of the footnote.   
My obvious problem is that \bibtitle or \bibhowpublished do not exist. I couldn't find a way to get the string values from a bib entry.

A:

BibLaTeX provides the entry type @online with url as one of the field. Thus you might want to consider to use this entry type to store website. 
One can define new types of citations using \DeclareCiteCommand, thus the way to define the command to print the title and the url in footnotes could be something like:
\DeclareCiteCommand{\wcite}
    [\mkbibfootnote]
    {}
    {\printfield{title}--\printfield{url}}
    {\addcomma\addspace}
    {}

The first argument is the name of  the command (\wcite); the second argument, an optional one, is to wrap the command (in this cases in a footnote, using the facility provided by BibLaTeX; the third argument is for a pre code; the fourth is for the content of the citation: the value of a field can be printed using \printfield{field name}; the fifth argument is for the code to be printed  between multiple citations; finally the last argument is for the postcode. 
To use the howpublished field replace \printfield{url} with \printfield{howpublished}
EDIT
It is possible to prevent the inclusion of web-site (@misc) in the bibliography by using the defenumbers option (the document must be compiled an even number of times after the bibliography has been generated)
\usepackage[defernumbers]{biblatex}

\printbibliography[nottype=misc]

