字符串操做

字符串的格式化：

str1 = "version"

num = 1.0

format = "%s" % str1

print(format)

format = "%s %d" % (str1, num)

print(format)

print('float : %f' % 1.25)

print('float : %.1f' % 1.25)

print('float : %.2f' % 1.25)

print("%(version)s : %(num).1f" % {"version":"version", "num":2})

word = "version3.0"

print(word.center(20))

print(word.center(20, "*"))

print(word.ljust(20))

print(word.rjust(20))

print("%30s" % word)

字符串轉義符：

path = "hello\tworld\n"

print(path)

print(len(path))

path = r"hello\tworld\n"

print(path)

print(len(path))

word = "\thello world\n"

print(word)

print("strip():", word.strip())

print("lstrip():", word.lstrip())

print("rstrip():", word.rstrip())

字符串合併：

strs = ['hello ', 'world ','hello ','China']

result = "".join(strs)

print(result)

字符串截取：

sentence = "Bob said: 1, 2, 3, 4"

print(sentence.split())

print(sentence.split(","))

print(sentence.split(",", 2))

字符串比較：

str1 = 1

str2 = '1'

if str1 == str2:

    print('same')

else:

    print('det')

    

if str(str1) == str2:

    print('same')

else:

    print('det')

word = "hello world"

print("hello" == word[0:5])

print(word.startswith("hello"))

print(word.endswith("ld", 6))

print(word.endswith("ld", 6, 10))

print(word.endswith("ld", 6, len(word)))

字符串反轉：

word = "hello world"

li = list(word)

li.reverse()

s = "".join(li)

print(s)

dlrow olleh

字符串查找：

sentence = "This is a apple."

print(sentence.find("a"))

sentence = "This is a apple."

print(sentence.rfind("a"))

字符串替換：

centence = "hello world, hello China"

print(centence.replace("hello","hi"))

print(centence.replace("hello","hi",1))

print(centence.replace("abc","hi"))