字串格式化

"""

字串格式化
"""msg = "i am" + " cql " + " abc" # 效率低,開闢記憶體空間大
print(msg)
# %s 可以接收一切
print("i am %s, %s" % ("aaa", [1 ,2]))
print("i am %s, %s" % ("aaa", 11))
print("i am %s, %s" % ("aaa", "aa"))
print("i am %s, %s" % ("aaa", (1, 2)))
# %d只能接收int型別
print("i am %s, %d" % ("aaa", 12))
# %f
print("i am %s, %f" % ("aaa", 12.0)) # i am aaa, 12.000000 預設顯示6位小數
print("i am %s, %.2f" % ("aaa", 12.0)) # i am aaa, 12.00 只顯示2位小數%.2f
print("i am %s, %.2f%%" % ("aaa", 12.0)) # i am aaa, 12.00%, %% 列印%
# format 字典形式
print("i am %(name)s age %(age)d" % ) # i am cql age 12
print("i am %(pp).2f" % ) # i am 19.89
# 寬度
print("i am %+20s" % "cql") # i am cql
# 按指定字元分隔組合顯示
print("root", "***", 0, 0, sep=":") # root:***:0:0

format

tpl = "i am {}, age {}, {}".format("seven", 18, 'alex')
tpl = "i am {}, age {}, {}".format(*["seven", 18, 'alex'])
tpl = "i am , age , really ".format("seven", 18)
tpl = "i am , age , really ".format(*["seven", 18])
tpl = "i am , age , really ".format(name="seven", age=18)
tpl = "i am , age , really ".format(**)
tpl = "i am , age , really ".format([1, 2, 3], [11, 22, 33])
tpl = "i am , age , money ".format("seven", 18, 88888.1)
tpl = "i am , age ".format(*["seven", 18])
tpl = "i am , age ".format(name="seven", age=18)
tpl = "i am , age ".format(**)
tpl = "numbers: ,,,,, ".format(15, 15, 15, 15, 15, 15.87623, 2)
print(tpl)
tpl = "numbers: ,,,,, ".format(15, 15, 15, 15, 15, 15.87623, 2)
tpl = "numbers: ,,,,, ".format(15)
tpl = "numbers: ,,,,, ".format(num=15)

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