I\m looking for solution that i can change the footer line to dashed line in fancyhdr. 
I just dont know how can i change the footer line to dashed line, what can i use, please give me a hint or something because I've been standing still for a days.
You can change the footer line with the command in your preamble
\renewcommand\footrule{\hdashrule{width}{height}{dash}}
where the command \hdashrule is from the dashrule package. You can see the package manual here.