Combination bag

A combination bag, comprising:

• a sling bag, wherein the sling bag comprises:
• a flat-shaped bag body with a first surface and a second surface facing away from each other, wherein the flat-shaped bag body is foldable;
• a rigid support structure embedded within the flat-shaped bag body, symmetrically arranged along a fold line of the flat-shaped bag body;
• a shoulder strap attached to the flat-shaped bag body;
• at least two bag components, wherein each of the bag components is positioned on the second surface of the flat-shaped bag body, for forming an independent storage compartment, and an opening of the independent storage compartment is located away from the fold line;
• a backpack with an interior space, wherein the interior space is defined by a first wall, a second wall opposite the first wall, and a continuous side wall connecting the first wall and second wall;
• wherein the first wall has an area approximately equal to that of the flat-shaped bag body, and flat-shaped bag body is detachably fixed within the interior space by a connecting component;
• when the flat-shaped bag body is fixed within the interior space, the first surface of the flat-shaped bag body is in close contact with the first wall.