学习python时,看到的一个题目
第一次写博客, 有误的地方还请大佬们指正,十分感谢~
要求如下
'''
文件存储格式如下:
id,name,age,phone,job(这行不需要写)
1,alice,22,13651156619,IT
2,ben,23,13310321345,Teacher
3,xiaoming,25,1331235342,IT
...
实现增删改查
1.查询:支持三种语法
select 列名1,列名2,... where 列名条件
支持大于小于等于,以及模糊查找(like)
select name,age where age>22 输出年龄大于22的人的名字和年龄
select * where job=IT 输出工作是IT的人的所有信息
select * where phone like 133 输出电话号包含133的人的所有信息
之后的增删改必须先登录,登录认证需要用装饰器完成
2.增:创建新员工记录,id要顺序增加
3.删除指定员工,直接输入员工id或名字即可
4.修改员工信息
语法: set 列名='新的值' where 条件
先用where查找对应人的信息,再用set修改列名对应的值为'新的值'
'''
1 import os
2 FLAG = False
3 tip = True
4 Account = '登入账号存放位置'
5 FileName = '员工信息文件存放位置'
6 def login(func):
7 def inner(*args, **kwargs):
8 if FLAG:
9 ret = func(*args, **kwargs)
10 return ret
11 else:
12 username = input('请登录后执行改操作!\n用户名:')
13 passwd = input('密码:')
14 if username and passwd:
15 with open(Account,'r',encoding='utf-8') as f:
16 read_lines = f.readlines()
17 if username == read_lines[0].strip() and passwd == read_lines[1].strip():
18 res = func(*args, **kwargs)
19 return ['登入成功', res]
20 else:
21 return '登入失败'
22 else:
23 return '登入失败'
24 return inner
25
26 @login
27 def select_operate(rec):
28 '''
29 查询操作函数第二版
30 接收处理后的列表
31 返回一个表示结果的列表
32 '''
33 rol_name = ['id', 'name', 'age', 'phone', 'job', '*']
34 res = []
35 def judge(rol_suoyin, tiaojian = rec[3]):
36 if '>=' in tiaojian:
37 tiaojian = tiaojian.split('>=')
38 tiaojian_before = tiaojian[0]
39 tiaojian_after = tiaojian[1]
40 if tiaojian_before in rol_name and tiaojian_after.isdigit():
41 tiaojian_suoyin = rol_name.index(tiaojian_before)
42 with open(FileName, 'r', encoding='utf-8') as f:
43 for line in f:
44 line = line.strip().split(',')
45 if int(line[tiaojian_suoyin]) >= int(tiaojian_after):
46 if rol_suoyin == 5:
47 res.append(line)
48 else:
49 res.append(line[rol_suoyin])
50 return res
51 else:
52 return '条件输入有误'
53 elif '<=' in tiaojian:
54 tiaojian = tiaojian.split('<=')
55 tiaojian_before = tiaojian[0]
56 tiaojian_after = tiaojian[1]
57 if tiaojian_before in rol_name and tiaojian_after.isdigit():
58 tiaojian_suoyin = rol_name.index(tiaojian_before)
59 with open(FileName, 'r', encoding='utf-8') as f:
60 for line in f:
61 line = line.strip().split(',')
62 if int(line[tiaojian_suoyin]) <= int(tiaojian_after):
63 if rol_suoyin == 5:
64 res.append(line)
65 else:
66 res.append(line[rol_suoyin])
67 return res
68 else:
69 return '条件输入有误'
70 elif '=' in tiaojian:
71 tiaojian = tiaojian.split('=')
72 tiaojian_before = tiaojian[0]
73 tiaojian_after = tiaojian[1]
74 if tiaojian_before in rol_name:
75 tiaojian_suoyin = rol_name.index(tiaojian_before)
76 with open(FileName, 'r', encoding='utf-8') as f:
77 for line in f:
78 line = line.strip().split(',')
79 if line[tiaojian_suoyin] == tiaojian_after:
80 if rol_suoyin == 5:
81 res.append(line)
82 else:
83 res.append(line[rol_suoyin])
84 return res
85 else:
86 return '条件输入有误'
87 elif '>' in tiaojian:
88 tiaojian = tiaojian.split('>')
89 tiaojian_before = tiaojian[0]
90 tiaojian_after = tiaojian[1]
91 if tiaojian_before in rol_name and tiaojian_after.isdigit():
92 tiaojian_suoyin = rol_name.index(tiaojian_before)
93 with open(FileName, 'r', encoding='utf-8') as f:
94 for line in f:
95 line = line.strip().split(',')
96 if int(line[tiaojian_suoyin]) > int(tiaojian_after):
97 if rol_suoyin == 5:
98 res.append(line)
99 else:
100 res.append(line[rol_suoyin])
101 return res
102 else:
103 return '条件输入有误'
104 elif '<' in tiaojian:
105 tiaojian = tiaojian.split('<')
106 tiaojian_before = tiaojian[0]
107 tiaojian_after = tiaojian[1]
108 if tiaojian_before in rol_name and tiaojian_after.isdigit():
109 tiaojian_suoyin = rol_name.index(tiaojian_before)
110 with open(FileName, 'r', encoding='utf-8') as f:
111 for line in f:
112 line = line.strip().split(',')
113 if int(line[tiaojian_suoyin]) < int(tiaojian_after):
114 if rol_suoyin == 5:
115 res.append(line)
116 else:
117 res.append(line[rol_suoyin])
118 return res
119 else:
120 return '条件输入有误'
121 else:
122 if rec[4] == 'like':
123 if tiaojian in rol_name:
124 tiaojian_suoyin = rol_name.index(tiaojian)
125 tiaojian_after = rec[5]
126 with open(FileName, 'r', encoding='utf-8') as f:
127 for line in f:
128 line = line.strip().split(',')
129 if tiaojian_after in line[tiaojian_suoyin]:
130 if rol_suoyin == 5:
131 res.append(line)
132 else:
133 res.append(line[rol_suoyin])
134 return res
135 else:
136 return '条件输入有误'
137 else:
138 return '条件输入有误'
139 if rec[1] in rol_name:
140 return judge(rol_name.index(rec[1]))
141 elif ',' in rec[1]:
142 rol_douhao_list = rec[1].split(',')
143 rol_number = len(rol_douhao_list)
144 dic = {'id': 0, 'name': 0, 'age': 0, 'phone': 0, 'job': 0}
145 judge_list = []
146 tiaojian = rec[3]
147 for i in rol_douhao_list:
148 if i not in rol_name:
149 return '列名输入有误'
150 dic[i] += 1
151 if rol_number <= 4:
152 if rol_number == 2:
153 r1, r2 = rol_douhao_list[0], rol_douhao_list[1]
154 if r1 == r2:
155 return '列名重复'
156 rol_suoyin1, rol_suoyin2 = rol_name.index(r1), rol_name.index(r2)
157 if '>' in tiaojian:
158 tiaojian = tiaojian.split('>')
159 tiaojian_before = tiaojian[0]
160 tiaojian_after = tiaojian[1]
161 if tiaojian_before in rol_name and tiaojian_after.isdigit():
162 tiaojian_suoyin = rol_name.index(tiaojian_before)
163 with open(FileName,'r',encoding='utf-8') as f:
164 for line in f:
165 line = line.strip().split(',')
166 if int(line[tiaojian_suoyin]) > int(tiaojian_after):
167 res.append([line[rol_suoyin1],line[rol_suoyin2]])
168 return res
169 else:
170 return '条件输入有误'
171 elif '<' in tiaojian:
172 tiaojian = tiaojian.split('<')
173 tiaojian_before = tiaojian[0]
174 tiaojian_after = tiaojian[1]
175 if tiaojian_before in rol_name and tiaojian_after.isdigit():
176 tiaojian_suoyin = rol_name.index(tiaojian_before)
177 with open(FileName,'r',encoding='utf-8') as f:
178 for line in f:
179 line = line.strip().split(',')
180 if int(line[tiaojian_suoyin]) < int(tiaojian_after):
181 res.append([line[rol_suoyin1],line[rol_suoyin2]])
182 return res
183 else:
184 return '条件输入有误'
185 elif '=' in tiaojian:
186 tiaojian = tiaojian.split('=')
187 tiaojian_before = tiaojian[0]
188 tiaojian_after = tiaojian[1]
189 if tiaojian_before in rol_name:
190 tiaojian_suoyin = rol_name.index(tiaojian_before)
191 with open(FileName,'r',encoding='utf-8') as f:
192 for line in f:
193 line = line.strip().split(',')
194 if line[tiaojian_suoyin] == tiaojian_after:
195 res.append([line[rol_suoyin1],line[rol_suoyin2]])
196 return res
197 else:
198 return '条件输入有误'
199 else:
200 if rec[4] == 'like':
201 if tiaojian in rol_name:
202 tiaojian_suoyin = rol_name.index(tiaojian)
203 tiaojian_after = rec[5]
204 with open(FileName, 'r', encoding='utf-8') as f:
205 for line in f:
206 line = line.strip().split(',')
207 if tiaojian_after in line[tiaojian_suoyin]:
208 res.append([line[rol_suoyin1],line[rol_suoyin2]])
209 return res
210 else:
211 return '条件输入有误'
212 else:
213 return '条件输入有误'
214 elif rol_number == 3:
215 r1, r2, r3= rol_douhao_list[0], rol_douhao_list[1], rol_douhao_list[2]
216 if r1 == r2 or r1 == r3 or r2 == r3:
217 return '列名重复'
218 rol_suoyin1, rol_suoyin2, rol_suoyin3 = rol_name.index(r1), rol_name.index(r2), rol_name.index(r3)
219 if '>' in tiaojian:
220 tiaojian = tiaojian.split('>')
221 tiaojian_before = tiaojian[0]
222 tiaojian_after = tiaojian[1]
223 if tiaojian_before in rol_name and tiaojian_after.isdigit():
224 tiaojian_suoyin = rol_name.index(tiaojian_before)
225 with open(FileName, 'r', encoding='utf-8') as f:
226 for line in f:
227 line = line.strip().split(',')
228 if int(line[tiaojian_suoyin]) > int(tiaojian_after):
229 res.append([line[rol_suoyin1], line[rol_suoyin2], line[rol_suoyin3]])
230 return res
231 else:
232 return '条件输入有误'
233 elif '<' in tiaojian:
234 tiaojian = tiaojian.split('<')
235 tiaojian_before = tiaojian[0]
236 tiaojian_after = tiaojian[1]
237 if tiaojian_before in rol_name and tiaojian_after.isdigit():
238 tiaojian_suoyin = rol_name.index(tiaojian_before)
239 with open(FileName, 'r', encoding='utf-8') as f:
240 for line in f:
241 line = line.strip().split(',')
242 if int(line[tiaojian_suoyin]) < int(tiaojian_after):
243 res.append([line[rol_suoyin1],line[rol_suoyin2], line[rol_suoyin3]])
244 return res
245 else:
246 return '条件输入有误'
247 elif '=' in tiaojian:
248 tiaojian = tiaojian.split('=')
249 tiaojian_before = tiaojian[0]
250 tiaojian_after = tiaojian[1]
251 if tiaojian_before in rol_name:
252 tiaojian_suoyin = rol_name.index(tiaojian_before)
253 with open(FileName, 'r', encoding='utf-8') as f:
254 for line in f:
255 line = line.strip().split(',')
256 if line[tiaojian_suoyin] == tiaojian_after:
257 res.append([line[rol_suoyin1],line[rol_suoyin2], line[rol_suoyin3]])
258 return res
259 else:
260 return '条件输入有误'
261 else:
262 if rec[4] == 'like':
263 if tiaojian in rol_name:
264 tiaojian_suoyin = rol_name.index(tiaojian)
265 tiaojian_after = rec[5]
266 with open(FileName, 'r', encoding='utf-8') as f:
267 for line in f:
268 line = line.strip().split(',')
269 if tiaojian_after in line[tiaojian_suoyin]:
270 res.append([line[rol_suoyin1],line[rol_suoyin2], line[rol_suoyin3]])
271 return res
272 else:
273 return '条件输入有误'
274 else:
275 return '条件输入有误'
276 elif rol_number == 4:
277 r1, r2, r3, r4 = rol_douhao_list[0], rol_douhao_list[1], rol_douhao_list[2], rol_douhao_list[3]
278 if r1 == r2 or r1 == r3 or r1 == r4 or r2 == r3 or r2 == r4 or r3 == r4:
279 return '列名重复'
280 rol_suoyin1, rol_suoyin2, rol_suoyin3, rol_suoyin4 = rol_name.index(r1), rol_name.index(r2), rol_name.index(r3), rol_name.index(r4)
281 if '>' in tiaojian:
282 tiaojian = tiaojian.split('>')
283 tiaojian_before = tiaojian[0]
284 tiaojian_after = tiaojian[1]
285 if tiaojian_before in rol_name and tiaojian_after.isdigit():
286 tiaojian_suoyin = rol_name.index(tiaojian_before)
287 with open(FileName, 'r', encoding='utf-8') as f:
288 for line in f:
289 line = line.strip().split(',')
290 if int(line[tiaojian_suoyin]) > int(tiaojian_after):
291 res.append([line[rol_suoyin1], line[rol_suoyin2], line[rol_suoyin3], line[rol_suoyin4]])
292 return res
293 else:
294 return '条件输入有误'
295 elif '<' in tiaojian:
296 tiaojian = tiaojian.split('<')
297 tiaojian_before = tiaojian[0]
298 tiaojian_after = tiaojian[1]
299 if tiaojian_before in rol_name and tiaojian_after.isdigit():
300 tiaojian_suoyin = rol_name.index(tiaojian_before)
301 with open(FileName, 'r', encoding='utf-8') as f:
302 for line in f:
303 line = line.strip().split(',')
304 if int(line[tiaojian_suoyin]) < int(tiaojian_after):
305 res.append([line[rol_suoyin1],line[rol_suoyin2], line[rol_suoyin3], line[rol_suoyin4]])
306 return res
307 else:
308 return '条件输入有误'
309 elif '=' in tiaojian:
310 tiaojian = tiaojian.split('=')
311 tiaojian_before = tiaojian[0]
312 tiaojian_after = tiaojian[1]
313 if tiaojian_before in rol_name:
314 tiaojian_suoyin = rol_name.index(tiaojian_before)
315 with open(FileName, 'r', encoding='utf-8') as f:
316 for line in f:
317 line = line.strip().split(',')
318 if line[tiaojian_suoyin] == tiaojian_after:
319 res.append([line[rol_suoyin1],line[rol_suoyin2], line[rol_suoyin3], line[rol_suoyin4]])
320 return res
321 else:
322 return '条件输入有误'
323 else:
324 if rec[4] == 'like':
325 if tiaojian in rol_name:
326 tiaojian_suoyin = rol_name.index(tiaojian)
327 tiaojian_after = rec[5]
328 with open(FileName, 'r', encoding='utf-8') as f:
329 for line in f:
330 line = line.strip().split(',')
331 if tiaojian_after in line[tiaojian_suoyin]:
332 res.append([line[rol_suoyin1],line[rol_suoyin2], line[rol_suoyin3], line[rol_suoyin4]])
333 return res
334 else:
335 return '条件输入有误'
336 else:
337 return '条件输入有误'
338 elif rol_number == 5:
339 for v in dic.values():
340 judge_list.append(v)
341 if judge_list == [1, 1, 1, 1, 1]:
342 return judge(5)
343 else:
344 return '列名重复'
345 else:
346 return '列名输入有误'
347 else:
348 return '列名输入有误或语法错误'
349
350 @login
351 def add_operate(rec):
352 '''
353 添加操作函数
354 接收处理后的列表
355 返回存放添加结果和所添加数据的列表
356 '''
357 if rec[1].isdigit() and rec[2].isdigit():
358 with open(FileName, 'a+', encoding='utf-8') as f:
359 f.seek(0)
360 for line in f:
361 yg_id = str(int(line.strip().split(',')[0])+1)
362 # for line in f:
363 # yg_id = line.strip().split(',')[0]
364 # yg_add = yg_id + ',' + ','.join(rec)
365 f.write(f'\n{yg_id},{",".join(rec)}')
366 return f'成功添加数据:{yg_id},{",".join(rec)}'
367 else:
368 return '输入错误'
369
370 @login
371 def del_operate(rec):
372 '''
373 删除操作函数
374 接收处理后的列表
375 返回存放删除结果和存放所删除结果的列表
376 '''
377 rec = ''.join(rec)
378 yg_dic = {}
379 del_line = []
380 def operate():
381 count = 0
382 re_count = 0
383 with open(FileName, encoding='utf-8') as f1,\
384 open(FileName+'.bak', 'w', encoding='utf-8') as f2:
385 read_lines = f1.readlines()
386 for line in read_lines:
387 line = line.split(',')
388 if rec not in line:
389 if count < len(read_lines)-2:
390 line = ','.join(line)
391 f2.write(line)
392 count += 1
393 continue
394 else:
395 line = ','.join(line).strip()
396 f2.write(line)
397 continue
398 del_line.append(','.join(line).strip())
399 re_count += 1
400 if re_count == 1:
401 yorn = input(f'删除数据:\n\t{del_line}\n确认删除(Y/N):')
402 if yorn.lower() == 'y':
403 os.remove(FileName)
404 os.rename(FileName+'.bak', FileName)
405 return f'删除数据成功:{del_line}'
406 else:
407 return f'删除数据操作取消'
408 else:
409 os.remove(FileName+'.bak')
410 l = []
411 for i in range(len(del_line)):
412 l.append(del_line[i]+'\n')
413 del_line_fail = '\t\t'.join(l).strip()
414 return f'ERROR:输入姓名重复(请尝试使用id删除)\n\t' \
415 f'重复数据如下:\n\t\t{del_line_fail}'
416 with open(FileName, encoding='utf-8') as f:
417 for line in f:
418 line = line.strip().split(',')
419 yg_dic.setdefault(line[0], line[1])
420 if rec in yg_dic or rec in yg_dic.values():
421 return operate()
422 # elif rec in yg_dic.values():
423 # return operate()
424 else:
425 return '输入错误'
426
427 @login
428 def update_operate(rec):
429 '''
430 修改操作函数(仅对唯一对象进行修改)
431 接收处理后的列表
432 返回存放修改结果和所修改对象的列表
433 '''
434 rol_name = ['id', 'name', 'age', 'phone', 'job']
435 if '=' in rec[1]:
436 rol = rec[1].split('=')[0]
437 new_data = rec[1].split('=')[1]
438 tiaojian = rec[3]
439 read_lines_suoyin = 0
440 count = 0
441 if rol in rol_name:
442 rol_suoyin = rol_name.index(rol)
443 with open(FileName, encoding='utf-8') as f:
444 read_lines = f.readlines()
445 if '=' in tiaojian:
446 tiaojian_before = tiaojian.split('=')[0]
447 if tiaojian_before in rol_name:
448 tiaojian_before_suoyin = rol_name.index(tiaojian_before)
449 tiaojian_after = tiaojian.split('=')[1]
450 for i in read_lines:
451 i = i.split(',')
452 # print(tiaojian_after, i[tiaojian_before_suoyin],tiaojian_after == i[tiaojian_before_suoyin])
453 # print(len(read_lines))
454 # print("i :", i, read_lines[len(read_lines)-1].split(','))
455 # print(i[tiaojian_before_suoyin] != tiaojian_after)
456 if i[tiaojian_before_suoyin].strip() == tiaojian_after:
457 count += 1
458 i[rol_suoyin] = new_data
459 updata_data = ','.join(i)
460 read_lines[read_lines_suoyin] = updata_data
461 if count > 1:
462 return '查询结果不唯一,无法修改'
463 if i == read_lines[len(read_lines)-1].split(',') and count == 0\
464 and i[tiaojian_before_suoyin] != tiaojian_after:
465 return '条件查询结果为空'
466 read_lines_suoyin += 1
467 with open(FileName+'.bak', 'w', encoding='utf-8')as f1:
468 for i in read_lines:
469 f1.write(f'{i}')
470 os.remove(FileName)
471 os.rename(FileName+'.bak', FileName)
472 return f'成功修改数据:{updata_data.strip()}'
473 else:
474 return '输入有误或语法错误'
475 else:
476 return '现仅支持条件为等于时的修改'
477 else:
478 return '输入有误或语法错误'
479 else:
480 return '语法错误'
481
482 def first_operate(rec):
483 '''
484 初步处理函数
485 接收用户输入对象并分割为列表
486 返回将要执行的函数
487 '''
488 rec = rec.split()
489 if len(rec)>= 4 and ("'" in rec[3] or '"' in rec[3]):
490 rec[3] = rec[3].replace("'", "", 2)
491 rec[3] = rec[3].replace('"', '', 2)
492 if rec[0] == 'select' and len(rec) >= 4 and rec[2] == 'where':
493 return select_operate(rec)
494 elif rec[0] == 'set' and len(rec) >= 4 and 'where' in rec:
495 return update_operate(rec)
496 elif len(rec) == 1:
497 return del_operate(rec)
498 elif len(rec) == 4:
499 return add_operate(rec)
500 else:
501 return '输入错误'
502
503 while 1:
504 if tip:
505 tip = False
506 print('输入help可查看各语句用法')
507 rec = input('>>>')
508 if rec.isspace():
509 print('输入错误')
510 elif rec == '':
511 continue
512 elif rec == 'exit' or rec == 'quit' or rec == '\q':
513 print('退出系统...')
514 break
515 elif rec == 'help' or rec == 'select -h' or rec == 'set -h':
516 if rec == 'help':
517 print(''' 1.文件存储格式为:id,name,age,phone,job
518 2.增加:直接按序输入姓名 年龄 手机号 工作即可 以空格间隔
519 3.查询:select 列名1,列名2,... where 列名条件
520 4.删除指定员工,直接输入员工id或名字即可
521 5.修改:set 列名='新的值' where 条件''')
522 elif rec == 'select -h':
523 print('查询:select 列名1,列名2,... where 列名条件')
524 elif rec == 'set -h':
525 print('修改:set 列名="新的值" where 条件')
526 else:
527 res = first_operate(rec)
528 print('结果如下:')
529 if type(res) == list:
530 if '登入成功' in res:
531 FLAG = True
532 for i in res:
533 if type(i) == list:
534 for j in i:
535 print(f'\t{j}')
536 else:
537 print(f'\t{i}')
538 elif res == []:
539 print('\t未查询到结果')
540 else:
541 for i in res:
542 if type(i) == list:
543 for j in i:
544 print(f'\t{j}', end=' ')
545 print('')
546 else:
547 print(f'\t{i}')
548 else:
549 print(f'\t{res}')
代码
以上~
