索引和切片

已经确定字符串是从零开始索引的，可以使用其索引值访问字符串中的任何元素。还可以通过在两个索引值之间进行切片来获取字符串的子集。例如：

main_string = "I learned English and Python with ZHouluobo. You can do it too!"
# Index 0
print(main_string[0])
# Index 1
print(main_string[1])
# Check if Index 1 is whitespace
print(main_string[1].isspace())
# Slicing 1
print(main_string[0:11])
# Slicing 2:
print(main_string[-18:])
# Slicing and concatenation
print(main_string[0:11] + ". " + main_string[-18:])

Output:

I
True
I learned English
You can do it too!
I learned English. You can do it too!