Python十个实例（五）

0x00 移除字符串中字符

str = input("请输入一个字符串：")
n = int(input("请输入要移除的字符位置："))

print("原始字符串为：" + str)

new_str = ""
for i in range(0,len(str)):
    if i != n:
        new_str = new_str + str[i]

print("字符串移除后为：" + new_str)

0x01 判断子字符串是否存在

str = input("请输入一个字符串：")
sub_str = input("请输入子字符串：")

if sub_str in str:
    print("子字符串存在！")
else:
    print("子字符串不存在！")

0x02 正则表达式提取URL

import re 
  
def Find(string): 
    # findall() 查找匹配正则表达式的字符串
    url = re.findall('https?://(?:[-\w.]|(?:%[\da-fA-F]{2}))+', string)
    return url 
      
string = 'Google 的网页地址为：https://www.google.com'
print("Urls: ", Find(string))

0x03 字符串翻转

str = input("请输入一个字符串：")

print("初始字符串为：" + str)
print("翻转字符串为：" + str[::-1])

0x04 字符串切片

def rotate(input,d): 
  
    Lfirst = input[0 : d] 
    Lsecond = input[d :] 
    Rfirst = input[0 : len(input)-d] 
    Rsecond = input[len(input)-d : ] 
  
    print( "头部切片翻转 : ", (Lsecond + Lfirst) )
    print( "尾部切片翻转 : ", (Rsecond + Rfirst) )
 
if __name__ == "__main__": 
    str = input("请输入一个字符串：")
    d = int(input("请输入切片长："))
    rotate(str,d)

0x05 字典排序

def dictionairy():  
  
    # 声明字典
    key_value ={}     
 
    # 初始化
    key_value[2] = 56       
    key_value[1] = 2 
    key_value[5] = 12 
    key_value[4] = 24
    key_value[6] = 18      
    key_value[3] = 323 
 
    print ("按键(key)排序:")   
 
    # sorted(key_value) 返回一个迭代器
    # 字典按键排序
    for i in sorted (key_value) : 
        print ((i, key_value[i]), end =" ") 
  
def main(): 
    # 调用函数
    dictionairy()              
      
# 主函数
if __name__=="__main__":      
    main()

0x06 计算字典值之和

def Sum(myDict):
    sum = 0
    for i in myDict:
        sum = sum + myDict[i]
    return sum

dict = {'a':100,'b':200,'c':300}
print("Sum：",Sum(dict))

0x07 移除字典键值对

test_dict = {'a':1,'b':2,'c':3,'d':4}

print("字典移除前：" + str(test_dict))

del test_dict['d']
print("字典移除后：" + str(test_dict))

0x08 合并字典

def Merge(dict1,dict2):
    dict3 = {**dict1, **dict2}
    return dict3

dict1 = {'a':1,'b':2}
dict2 = {'c':3,'d':4}
dict3 = Merge(dict1,dict2)

print(dict3)

0x09 时间戳转换

import time
 
a1 = "2019-5-10 23:40:00"
# 先转换为时间数组
timeArray = time.strptime(a1, "%Y-%m-%d %H:%M:%S")
 
# 转换为时间戳
timeStamp = int(time.mktime(timeArray))
print(timeStamp)
 
 
# 格式转换 - 转为 /
a2 = "2019/5/10 23:40:00"
# 先转换为时间数组,然后转换为其他格式
timeArray = time.strptime(a2, "%Y/%m/%d %H:%M:%S")
otherStyleTime = time.strftime("%Y/%m/%d %H:%M:%S", timeArray)
print(otherStyleTime)