The ornamental design for a computercase, as shown and described.
FIG. 1 is a perspective view of a computer case showing our new design;
FIG. 2 is a front view thereof;
FIG. 3 is a rear view thereof;
FIG. 4 is a left side view thereof;
FIG. 5 is a right side view thereof;
FIG. 6 is a top plan view thereof;
FIG. 7 is a bottom plan view thereof;
FIG. 8 is another perspective view thereof in an alternative position of use;
FIG. 9 is another perspective view thereof in an alternative position of use; and,
FIG. 10 is another perspective view thereof in an alternative position of use.
The broken lines showing of a keyboard and screen detail are included for the purpose of illustrating environment and form no part of the claimed design.