How to colour a table with opaque colour such that no text and no lines are visible?
\color{green}
before the table will color the lines and text
\documentclass[border=3.14]{standalone}
\usepackage[table]{xcolor}
\begin{document}
\colorbox{green}{
\color{green}
\begin{tabular}{| c | c |}
a & b \\
c & d \\
\end{tabular}}
\end{document}
I'm not sure whether I understood your question correctly or not. The following typesets its argument inside a box and outputs a green box which has the same size as the argument would have had.
\documentclass[]{article}
\usepackage{xcolor}
\usepackage{grabbox}
\newsavebox\overgreenboxBox
\newcommand*\overgreenbox
{%
\grabbox\overgreenboxBox\hbox
{%
\textcolor{green}
{%
\vrule
height \ht\overgreenboxBox
depth \dp\overgreenboxBox
width \wd\overgreenboxBox
}%
}%
}
\begin{document}
\overgreenbox{\begin{tabular}{| c | c |}a&b\\c&d\\\end{tabular}}
\end{document}
You can colourise both cell background and text using the same colour for text and background. If you load the array-package, you can define a new column type G (for green). \arrayrulecolor
colourise the lines. Depending of your goals; with this approach you can change each of the three coloured item individually:
\documentclass[border=3.14]{standalone}
\usepackage[table]{xcolor}
\usepackage{array}
\newcolumntype{G}{>{\cellcolor{green}\color{green}}{c}}
\arrayrulecolor{green} % Colourise rule for all tabulars, move inside the tabular environment to limit scope
\begin{document}
\begin{tabular}{| * {2}{G|}}
a & b \\
c & d \\
\end{tabular}
\end{document}