学习python：（三）list的增删改查

今天学习了list的增删改查:

增：append()  extend() 

删del（）

改：改list元素 

查：截取数据，list长度检查；

并学习了如何返回list的下标以及下标和数据。代码如下：

'''
学习python：（三）list的增删改查
'''


def test():
    mylist = ['a', 'b', 'c', 1, 2, 3]
    '''
    查
    '''
    print(mylist[0:])
    print(mylist[:-1])
    print(len(mylist))
    '''
    增
    '''
    mylist.append('d')
    print(mylist)
    mylist.extend([4, 5])
    print(mylist)

    '''
    改
    '''
    mylist[0] = 'm'
    print(mylist)
    mylist[0:2] = 'q', 'n'
    print(mylist)
    '''
    删
    '''
    del mylist[0]
    print(mylist)
    del mylist[0:1]
    print(mylist)
    mylist1 = [6, 7, 8]
    '''
    拼接
    '''
    mylist2 = mylist + mylist1
    print(mylist2)
    return len(mylist2)


def test1():
    print("mylist2的长度是:", test())


def testteach():
    '''
    输出list的下标
    输出list的下标和数据
    :return:
    '''
    mylist = ['a', 'b', 'c', 1, 2, 3]
    for i in range(len(mylist)):
        print(i)
    for i, j in enumerate(mylist):
        print("下标：", i, "value:", j)


if __name__ == '__main__':
    test1()
# testteach()