在腳本中顯示時修改字符串

Question

我試圖弄清楚如何編寫一個bash腳本，在約0:55處做這樣的事情，其中​​字符在不斷變化 -/\ | https://www.youtube.com/watch?v=ZwK2NReSRFU

我怎麼會做這樣的事情，但有做第二刪除之前的第一echo命令？

echo "hello" 
sleep 1 
echo "Hello" 
sleep 1 
echo "hEllo" 
slep 1 
echo "heLlo" 

等

Answer 1

您需要存儲和恢復光標位置，並清除當前行。這完成使用ANSI terminal escape sequences：

echo -en "\033[s" # Save cursor position 
while true ; do 
    echo -n "hello" 
    sleep 1 
    echo -en "\033[1K" # Clear current line 
    echo -en "\033[u" # Restore cursor position 
    echo -n "Hello" 
    sleep 1 
    echo -en "\033[1K" 
    echo -en "\033[u" 
    echo -n "hEllo" 
    sleep 1 
    echo -en "\033[1K" 
    echo -en "\033[u" 
    echo -n "heLlo" 
    sleep 1 
    echo -en "\033[1K" 
    echo -en "\033[u" 
    echo -n "helLo" 
    sleep 1 
    echo -en "\033[1K" 
    echo -en "\033[u" 
    echo -n "hellO" 
    sleep 1 
    echo -en "\033[1K" 
    echo -en "\033[u" 
done