1 1,Alex Li,22,13651054608,IT,2013-04-01

1,Alex Li,22,13651054608,IT,2013-04-012,Jack Wang,30,13304320533,HR,2015-05-033,Rain Liu,25,1383235322,Sales,2016-04-224,Mack Cao,40,1356145343,HR,2009-03-01

import osdef select(data):    """    查询语法一：select name,age from staff_table where age > 22    查询语法二：select * from staff_table where dept = IT    查询语法三：select  * from staff_table where enroll_date like "2013"    """    data1 = data.split()    if data =http://www.mamicode.com/= (‘select name,age from staff_table where age > %s‘ %(data1[7])):        with open("aaa.txt", encoding="utf-8") as f:            list = []            for line in f:                i = line.strip().split(",")                a = i[1]                b = i[2]                c = [a, b]                if b > data1[7]:                    list.append(c)            for i in list:                print(‘,‘.join(i))            print("查询到%s条符合的信息" %len(list))    elif data =http://www.mamicode.com/= (‘select * from staff_table where dept = %s‘ %(data1[7])):        with open("aaa.txt", encoding="utf-8") as f2:            list2 = []            for line in f2:                i = line.strip().split(",")                if data1[7]==i[4]:                    list2.append(i)            for i in list2:                print(‘,‘.join(i))            print("查询到%s条符合的信息" %len(list2))    elif data =http://www.mamicode.com/= (‘select  * from staff_table where enroll_date like %s‘ % (data1[8])):        with open("aaa.txt", encoding="utf-8") as f3:            list3 = []            for line in f3:                i = line.strip().split(",")                if data1[8].strip(‘""‘) == i[5][:4]:                    list3.append(i)            for i in list3:                print(‘,‘.join(i))            print("查询到%s条符合的信息" %len(list3))def add(data):     """     添加语法： name,age,phone,dept,enroll-date     (例如：张,22,123456789,IT,2017-06-18)     """     data1 = data.split(",")     with open("aaa.txt",encoding="utf-8")as f:         list = []         phone_list = []         for line in f:             i = line.strip().split(",")             phone_list.append(i[3])         if data1[2] in phone_list:            print("phone已存在")         else:             with open("aaa.txt", "r+", encoding="utf-8")as f:                 for line in f:                     i = line.strip().split(",")                     # print(i)                     list.append(i)                 w = str(int(list[-1][0]) + 1)                 data1.insert(0, w)                 data1 = ‘,‘.join(data1)                 f.write(‘\n‘+data1)                 print(data1+‘\n‘"添加成功!!!")def delete(data):    """    删除语法：delete from staff_table where staff_id = 12    """    data1 = data.split(" ")    if data =http://www.mamicode.com/= ("delete from staff_table where staff_id = %s" %data1[6]):        with open("aaa.txt", encoding="utf-8") as f:            for line in f:                i = line.strip().split(",")                if data1[6] == i[0]:                    i2 = ‘,‘.join(i)                    print(i2)        with open("aaa.txt", encoding="utf-8")as f_read,open("aaa_back.txt", "a+", encoding="utf-8")as f_write:            for i in f_read:                if i2 in i:                    i = i.replace(i2, "").strip()                f_write.write(i)                # f_write.flush()        os.remove("aaa.txt")        os.rename("aaa_back.txt","aaa.txt")        print("删除成功！！！")def change(data):    """    修改语法：UPDATE staff_table SET dept="Market" WHERE where dept = "IT"    """    data1 = data.split()    with open("aaa.txt", encoding="utf-8") as f_read,open("aaa_back.txt","w",encoding="utf-8")as f_write:        for line in f_read:            if  data1[3][6:-1] in line:                line = line.replace(data1[3][6:-1],data1[8][1:-1])            f_write.write(line)            # f_write.flush()    os.remove("aaa.txt")    os.rename("aaa_back.txt","aaa.txt")    print("修改成功!!!")if __name__ == "__main__":    msg = """    1:查询    2:添加    3:删除    4:修改    5:退出    """    msg_dict = {     "1": select,     "2": add,     "3": delete,     "4": change,     "5": exit,    }    while True:        print(‘员工信息文件的增删改查:\n‘+msg)        choice = input("输入编号>>:").strip()        if len(choice) == 0 or choice not in msg_dict: continue        if choice ==‘5‘:break        else:            print(msg_dict[choice].__doc__)        data = input("请输入语法或返回上一级(b):").strip()        if len(data) == 0:continue        elif data.lower()==‘b‘:            continue        msg_dict[choice](data)