Minimizing your carbohydrate intake is important in maintaining your weight. For more years than I care to remember a sandwich was a lunchtime staple.
I modified it over the years, switching to whole wheat and multi-grain and then a wrap. Now I eliminate that altogether and use my protein ( ie. a slice of meat) as the outer shell.
I typically use roast beef, turkey or ham. My typical filler is broccoli rabe steamed in a microwave and eggplant that was grilled with olive oil. I slice and grill my eggplant on Sunday and put it in a plastic container and use it during the week. I put the broccoli rabe in a plastic bowl and microwave for 12 minutes with a lid on and also refrigerate and use during the week.
I take a slice of meat, lay on some eggplant and broccoli rabe and roll up.