紀錄一下如何在cli上呈現不同的顏色
在使用golang時，發現fmt以及log印出來的字除了多了時間以外還多了點顏色。
好奇之下才去搜尋了一下關於golang顏色字串的教學。
強力推薦這篇StackOverFlow的文章
查了一下才發現原來顏色字串這件事情，其實要歸到ANSI-Colors這個功能。
1.首先你的文字介面器要可以支援ansi escape code
Unix-like的系統應該都支援，windows 的 Powershell也支援。
2.規則
溢出字元 "\033"
指令規則:"\033[{code1};{code2};{code3}m"
3.範例
紫色字串:"\033[35m"(code參考下列色碼表)
package main
import (
"fmt"
)
func main() {
fmt.Println()
fmt.Println("\033[35m你好")
fmt.Println("你好")
fmt.Println()
}
輸出:
因為指令"\033[35m"所以之後的字串顏色都變成紫色的
還原指令: "\033[0m"
package main
import (
"fmt"
)
func main() {
fmt.Println()
fmt.Println("\033[35m你好\033[0m \033[31m我好\033[0m \033[32m大家好\033[0m")
fmt.Println()
}
輸出:
加上背景色:
package main
import (
"fmt"
)
func main() {
fmt.Println()
fmt.Println("\033[37;101m危險\033[0m")
fmt.Println()
}
輸出:
其他像是粗體字，下底線等等code請參考附件表格。
4.懶人包
如果懶得自己處理溢出字元指令，github上也有人分享包裝好的package方便使用。
詳細可自行參考github說明
安裝 :go get github.com/fatih/color
package main
import (
"fmt"
"github.com/fatih/color"
)
func main() {
fmt.Println()
color.Cyan("Prints text in cyan.")
fmt.Println()
}
輸出:
參考附件
色碼表:
指令表:
╔══════════╦════════════════════════════════╦═════════════════════════════════════════════════════════════════════════╗
║ Code ║ Effect ║ Note ║
╠══════════╬════════════════════════════════╬═════════════════════════════════════════════════════════════════════════╣
║ 0 ║ Reset / Normal ║ all attributes off ║
║ 1 ║ Bold or increased intensity ║ ║
║ 2 ║ Faint (decreased intensity) ║ Not widely supported. ║
║ 3 ║ Italic ║ Not widely supported. Sometimes treated as inverse. ║
║ 4 ║ Underline ║ ║
║ 5 ║ Slow Blink ║ less than 150 per minute ║
║ 6 ║ Rapid Blink ║ MS-DOS ANSI.SYS; 150+ per minute; not widely supported ║
║ 7 ║ [[reverse video]] ║ swap foreground and background colors ║
║ 8 ║ Conceal ║ Not widely supported. ║
║ 9 ║ Crossed-out ║ Characters legible, but marked for deletion. Not widely supported. ║
║ 10 ║ Primary(default) font ║ ║
║ 11–19 ║ Alternate font ║ Select alternate font `n-10` ║
║ 20 ║ Fraktur ║ hardly ever supported ║
║ 21 ║ Bold off or Double Underline ║ Bold off not widely supported; double underline hardly ever supported. ║
║ 22 ║ Normal color or intensity ║ Neither bold nor faint ║
║ 23 ║ Not italic, not Fraktur ║ ║
║ 24 ║ Underline off ║ Not singly or doubly underlined ║
║ 25 ║ Blink off ║ ║
║ 27 ║ Inverse off ║ ║
║ 28 ║ Reveal ║ conceal off ║
║ 29 ║ Not crossed out ║ ║
║ 30–37 ║ Set foreground color ║ See color table below ║
║ 38 ║ Set foreground color ║ Next arguments are `5;n` or `2;r;g;b`, see below ║
║ 39 ║ Default foreground color ║ implementation defined (according to standard) ║
║ 40–47 ║ Set background color ║ See color table below ║
║ 48 ║ Set background color ║ Next arguments are `5;n` or `2;r;g;b`, see below ║
║ 49 ║ Default background color ║ implementation defined (according to standard) ║
║ 51 ║ Framed ║ ║
║ 52 ║ Encircled ║ ║
║ 53 ║ Overlined ║ ║
║ 54 ║ Not framed or encircled ║ ║
║ 55 ║ Not overlined ║ ║
║ 60 ║ ideogram underline ║ hardly ever supported ║
║ 61 ║ ideogram double underline ║ hardly ever supported ║
║ 62 ║ ideogram overline ║ hardly ever supported ║
║ 63 ║ ideogram double overline ║ hardly ever supported ║
║ 64 ║ ideogram stress marking ║ hardly ever supported ║
║ 65 ║ ideogram attributes off ║ reset the effects of all of 60-64 ║
║ 90–97 ║ Set bright foreground color ║ aixterm (not in standard) ║
║ 100–107 ║ Set bright background color ║ aixterm (not in standard) ║
╚══════════╩════════════════════════════════╩═════════════════════════════════════════════════════════════════════════╝
參考:
https://stackoverflow.com/questions/4842424/list-of-ansi-color-escape-sequences
https://en.wikipedia.org/wiki/ANSI_escape_code
https://github.com/fatih/color
