python實現增刪改查操作

# 增加操作
# append在列表的尾部加入指定的元素
name_list = ["小明","小強","小紅"]
name_list.append("小花")
print(name_list)

# extend將指定序列的元素依次追加到列表的尾部(合並),不會去重復內容
# name_list2 = ["小豬","小貓",'小明']
# name_list.extend(name_list2)
# print(name_list)
#
# # " + "加法 等價於 extend 方法
# name_list3=name_list+name_list2
# print(name_list3)
#
# # insert將指定的元素插入到對應的索引位上，注意負索引倒序插入，超過索引就會在末尾插入
# name_list.insert(0,"小尹")
# name_list.insert(-3,"小黃")
# print(name_list)

# 刪除操作
# pop彈出，返回並刪除指定索引位上的數據，默認刪除索引為-1的數據(從右向左刪除)
# name = name_list.pop(1)
# print(name)
# #指定索引刪除
# print(name_list)
# del刪除整個列表或列表的數據，del是python內置功能，不是列表獨有的
# del name_list[0]
# print(name_list)
# remove刪除一個指定的元素
# name_list.remove("小強")
# print(name_list)
# clear 清空列表
# name_list.clear()
# print(name_list)


# 修改操作
# name_list[0]="小白"
# print(name_list)

# 查找操作
# 使用索引
name_list=["tom","jerry","array","tom"]
# name=name_list[2]
# print(name)
# index查找，從左往右返回查找到的第一個指定元素的索引，如果沒有找到，報錯
# index=name_list.index("jerry")
# print(index)
# count計數，返回要計數的元素在列表當中的個數
num=name_list.count("tom")
print(num)

# 默認排序
# lst1=["abd","ABD","aBe"]
# lst1.sort()
# print(lst1)

# 指定排序規則
# lst1=["abd","ABD","aBc"]
# lst1.sort(key=str.lower)
# print(lst1)
# # reverse()翻轉
# lst1=["abc","ABD","aBe"]
# lst1.reverse()
# print(lst1) # ["aBe","ABD","abc"]
# lst1=["abc","ABD","aBe"]
# print(lst1)
# lst2=sorted(lst1)
# print(lst2) # ["ABD","aBe","abc"]
# lst3=sorted(lst1,key=str.lower)
# print(lst3) # ["abc","ABD","aBe"]
# lst4=sorted(lst1,reverse=True)
# print(lst4) # ["abc","aBe","ABD"]