场景需要将Excel中的数据导入到数据库中，就会用到文件上传的功能。这里使用ElementUI的el-upload控件实现文件上传。 注： 关注公众号 霸道的程序猿 获取编程相关电子书、教程推送与免费下载。实现首先在页面上添加一个el-upload控件<el-upload ref="upload" :limit="1" accept=".x
当你学了一段时间爬虫后，就会知道各种功能太多而且麻烦。还不如自己整理个框架方便的多。因此，从开始写爬虫程序开始，就会慢慢的接触到一些有关爬虫的框架、效率提升而且扩展也很方便。接下来我将会以Scrapy爬虫框架将我的学习过程记录下供大家参考指正。
一、异常异常:---异于平常异常即是事件，该事件会在程序执行过程中发生，影响程序的正常执行。即使语句或表达式使用了正确的语法，执行时仍然可能触发错误。执行行检测到的错误称为异常。错误和异常1、语法错误和逻辑错误a = 90if a > 100 print('哈哈')2、逻辑错误print(1/0)3、异常处理：出现了异常，通过做异常捕获（异常处理）之后，不会影响后续代码的执行print
场景在管理系统中，时间的存储、查询、显示的格式往往需要统一。这就涉及到在数据库中存储时间，使用Mybatis对时间进行比较查询，使用Springboot中的实体类存储查询时间，使用前端时间选择器，这里是ElementUI的时间选择器。注：关注公众号 霸道的程序猿 获取编程相关电子书、教程推送与免费下载。实现首先是数据库中表的设计，关于时间字段，设计为Date类型 数据库中对于时间的存储没
个app与权限关联表。首先设计app表这里是存储的APP对象的一些属性，即一对多.
场景双击el-table的某个单元格时获取此单元格的信息并弹窗显示其他关联的信息。效果如下 注：关注公众号 霸道的程序猿 获取编程相关电子书、教程推送与免费下载。实现首先给el-table设置cell-dblclick事件<el-table v-loading="loading" :data="kqryszList" @sele
n this problem, you have to analyze a particular sorting al
Matrix Chain MultiplicationTime Limit: 1000MS Memory Limit: 65536KTotal Submissions: 1695 Accepted: 1090DescriptionSuppose you have to evaluate an expression like A
Score InflationThe more
Controlling CompaniesSome companies are partial owners of other companies because they have acquired part of their total shares of stock. For example, Ford owns 12% of Mazda. It is said that a com
: 1710DescriptionThere is a square wall which is made of n*n small square br
FatMouse and CheeseTime Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others) Total Submission(s): 2977 Accepted Submission(s): 1160
Problem
H. Queries for Number of Palindromestime limit per test5 secondsmemory limit per test256 megabytesinputstandard inputoutputstandard outputYou've got a string s = s1s2...
Riding the Fences
Farmer John owns a large number of fences that must be repaired annually. He traverses the fences by riding a horse along each and every one of them (and nowhere else) and fixi
Safe Or Unsafe Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others) Total Submission(s): 863 Accepted Submission(s): 309
Problem Descri
Problem Description
For each prefix of a g
D - Seller Bob
Crawling in process...Crawling failedTime
Limit:2000MS Memory Limit:131072KB
bit IO Format:%Id & %Iu
SubmitStatusPracticeCodeForces
18D
Description
Last year
Complete the Sequence
Time Limit: 3000/1000 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others)
Total Submission(s): 161 Accepted Submission(s): 93
Problem Description
You proba
E - CamelsCrawling in process...Crawling failedTime Limit:2000MS Memory Limit:65536KB bit IO Format:%Id & %IuSubmitStatusPracticeCodeForces 14EDescriptionBob likes to dr
A + B Problem TooTime Limit: 3000/1000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others) Total Submission(s): 8373 Accepted Submission(s): 6277
Problem D
C. Sequencetime limit per test1 secondmemory limit per test megabytesinputstandard inputoutputstandard outputLittle Petya likes to play very much. And most of all he li
E. Holestime limit per test1 secondmemory limit per test megabytesinputstandard inputoutputstandard outputLittle Petya likes to play a lot. Most of all he likes to play
Human Gene FunctionsTime Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others) Total Submission(s): 1506 Accepted Submission(s): 840
Problem
Raucous Rockers You just inherited the rights to N (1 <= N <= 20) previously unreleased songs recorded by the popular group Raucous Rockers. You plan to release a set of M (1 <= M <= 20
Longest path on DAGFind the longest path on directed acyclic graph G.InputThe first line contains two integers n, m, which denote the number of vertices and edges.The following m l
搬寝室
Problem Description
搬寝室是很累的,xhd深有体会.时间追述2
{ int z,zz=9999999;
go[x]=1;
if(x==1){go[x]=0;return 0;}
Problem Description
A projec
C - Bulls and Cows
Time Limit:2000MS Memory Limit:262144KB bit IO Format:%Id & %Iu
Submit
Status&nbs
monkeyTime Limit 1000msMemory Limit 65536Kdescription Cc is a lovely monkey. It likes to play the game "catching plates". The game is as f