Box-drawing character

Framing characters are graphical characters, which are mainly used for character-based user interface, where they are used to represent windows in text mode. It is a special type of block graphics.

History

Frame characters are encoded in varying degrees in different character sets. They normally include horizontal and vertical frame members, the four corners, the four tees and a Cross in various designs, such as simple and as a double border, but partly also in different frame thicknesses. Even characters that combine different types of frames, are often present.

The very first home computers used a variety of frame character, such as in CBM ASCII character set of Commodore. The encoding used for teletext includes framing characters.

The DOS code page 437 contains in the range B0hex to DFhex besides shades and block elements frame 40 characters. In other code pages are the frame character, in which a double line collides with a simple, partially replaced by other characters, so no mixed frame can be represented as the code page 850.

The escape sequences with those on the VT100 simple frame character could be produced, were taken on many Unix systems.

In Unicode frame 128 characters in Unicode block drawing frame coded, including, besides the characters of DOS code pages also characters from other encodings such as KS X 1001 and GB2312, but also a number of industry standards.

Examples

Single and double frame

┌ ─ ─ ┬ ─ ─ ┐ ╔ ═ ═ ╦ ═ ═ ╗ ╒ ═ ═ ╤ ═ ═ ╕ ╓ ─ ─ ╥ ─ ─ ╖ │ │ │ ║ ║ ║ │ │ │ ║ ║ ║ ├ ─ ─ ┼ ─ ─ ┤ ╠ ═ ═ ╬ ═ ═ ╣ ╞ ═ ═ ╪ ═ ═ ╡ ╟ ─ ─ ╫ ─ ─ ╢ │ │ │ ║ ║ ║ │ │ │ ║ ║ ║ └ ─ ─ ┴ ─ ─ ┘ ╚ ═ ═ ╩ ═ ═ ╝ ╘ ═ ═ ╧ ═ ═ ╛ ╙ ─ ─ ╨ ─ ─ ╜ Window with scroll bar

╔════════════════════════════════════[×]═╗ ║ ║ window title ╟──────────────────────────────────────┬─╢ ║ │ ▲ ║ window content ║ │ ░ ║ ║ │ ░ ║ ║ │ ░ ║ ║ │ ░ ║ ║ │ █ ║ ║ │ ░ ║ ║ │ ░ ║ ║ │ ░ ║ ║ │ ░ ║ ║ │ ░ ║ ║ │ ░ ║ ║ │ ░ ║ ║ │ ▼ ║ ╚══════════════════════════════════════╧═╝ alternatives

Instead of using frame characters simple framework can also be designed as ASCII art. However, in contrast to the frame characters here are gaps, so that no closed frame is possible.