static ProblemRepository()
{
User yh1 = new User("28zhu", "mima1!"),
yh2 = new User("WhiteWater", "mima2!");
Keyword CSharp = new Keyword("C#"),
JAVA = new Keyword("JAVA"),
Windows = new Keyword("Windows"),
Linux = new Keyword("Linux"),
CPlusPlus = new Keyword("C++");
string title1 = "有一个自定义UI控件，此控件使用在不同的系统中会有不同的呈现，之前的做法是各种switch case，阅读代码时让人很难受，另外新创建一个用到此控件的系统，要修改代码的地方也多，只要有swich case 的地方都要再加一个case。请教一个好一些的方式来处理这个问题，目的是让代码更加清楚",
title2 = "手动导入jar包，运行报错的问题";
string body1 = "RT，也不知道描述的清楚不清楚。求一个思路",
body2 = "运行就报这个错误，这个jar包我导入项目了的，不然编译都无法通过。";
problems = new List <Problem>
{
new Problem(body1, yh1)
{
Title = title1,
KeyWords = new List <Keyword>
{
CSharp,
CPlusPlus,
JAVA
}
},
new Problem(body2, yh1)
{
Title = title2,
KeyWords = new List <Keyword>
{
CSharp,
Linux
}
},
new Problem(body2, yh2)
{
Title = title2,
KeyWords = new List <Keyword>
{
CSharp,
CPlusPlus,
Windows
}
},
new Problem(body1, yh1)
{
Title = title1,
KeyWords = new List <Keyword>
{
CSharp,
CPlusPlus,
JAVA
}
},
new Problem(body2, yh2)
{
Title = title2,
KeyWords = new List <Keyword>
{
CSharp,
CPlusPlus,
Windows
}
},
new Problem(body2, yh2)
{
Title = title2,
KeyWords = new List <Keyword>
{
CSharp,
CPlusPlus,
Windows
}
},
new Problem(body1, yh1)
{
Title = title1,
KeyWords = new List <Keyword>
{
CSharp,
CPlusPlus,
JAVA
}
},
new Problem(body2, yh2)
{
Title = title2,
KeyWords = new List <Keyword>
{
CSharp,
CPlusPlus,
Windows
}
},
new Problem(body1, yh1)
{
Title = title1,
KeyWords = new List <Keyword>
{
CSharp,
CPlusPlus,
JAVA
}
},
new Problem(body1, yh1)
{
Title = title1,
KeyWords = new List <Keyword>
{
CSharp,
CPlusPlus,
JAVA
}
},
new Problem(body2, yh2)
{
Title = title2,
KeyWords = new List <Keyword>
{
CSharp,
CPlusPlus,
Windows
}
}
};
foreach (var item in problems)
{
ContentService.Publish(item);
}
}
static ExerciseOfLinq()
{
fg = new User {
Name = "飞哥"
};
xy = new User {
Name = "小余"
};
sql = new Keyword {
Content = "SQL"
};
csharp = new Keyword {
Content = "C#"
};
net = new Keyword {
Content = ".NET"
};
java = new Keyword {
Content = "JAVA"
};
js = new Keyword {
Content = "JAVASCRIPT"
};
html = new Keyword {
Content = "HTML"
};
SQL = new Article("文章")
{
Author = fg, Title = "SQL", Keywords = new List <Keyword> {
sql
}
};
JAVA = new Article("文章")
{
Author = fg, Title = "JAVA", Keywords = new List <Keyword> {
java, html
}
};
UI = new Article("文章")
{
Author = xy, Title = "UI", Keywords = new List <Keyword> {
js, html, net
}
};
CSharp = new Article("文章")
{
Author = xy, Title = "CSharp", Keywords = new List <Keyword> {
csharp
}
};
wx = new Comment(JAVA)
{
Body = "写的不行", Author = new User {
Name = "王欣"
}
};
atai = new Comment(SQL)
{
Body = "写的很好", Author = new User {
Name = "阿泰"
}
};
pzq = new Comment(UI)
{
Body = "还可以", Author = new User {
Name = "彭志强"
}
};
cbw = new Comment(CSharp)
{
Body = "一般般", Author = new User {
Name = "陈百万"
}
};
ljp = new Comment(CSharp)
{
Body = "看得下去", Author = new User {
Name = "刘江平"
}
};
SQL.Comments = new List <Comment> {
atai
};
JAVA.Comments = new List <Comment> {
wx
};
UI.Comments = new List <Comment> {
pzq
};
CSharp.Comments = new List <Comment> {
cbw, ljp
};
sql.Articles = new List <Article> {
SQL
};
csharp.Articles = new List <Article> {
CSharp
};
net.Articles = new List <Article> {
UI
};
java.Articles = new List <Article> {
JAVA
};
js.Articles = new List <Article> {
UI
};
html.Articles = new List <Article> {
JAVA, UI
};
articles = new List <Article> {
SQL, JAVA, UI, CSharp
};
ContentService.Publish(UI);
ContentService.Publish(CSharp);
ContentService.Publish(SQL);
ContentService.Publish(JAVA);
ide = new Problem("求助")
{
Author = fg, Reward = 5, Title = "哪个ide好用"
};
rj = new Problem("求助")
{
Author = fg, Reward = 8, Title = "这个软件怎么样"
};
php = new Problem("求助")
{
Author = xy, Reward = 7, Title = "php语法"
};
css = new Problem("求助")
{
Author = xy, Reward = 6, Title = "css怎么写"
};
problems = new List <Problem> {
ide, rj, php, css
};
}
public static void LinqDo()
{
User pzq = new User("彭志强", "555s@5")
{
HelpMoney = 100, HelpCradit = 100
};
User xlt = new User("幸龙泰", "sdoj&8")
{
HelpMoney = 100, HelpCradit = 100
};
User cy = new User("陈元", "8855*h")
{
HelpMoney = 100, HelpCradit = 100
};
User fg = new User("飞哥", "123ab!")
{
HelpMoney = 100, HelpCradit = 100
};
User xy = new User("小余", "123kk*")
{
HelpMoney = 100, HelpCradit = 100
};
Keyword sql = new Keyword("SQL");
Keyword js = new Keyword("JS");
Keyword html = new Keyword("html");
Keyword css = new Keyword("css");
Keyword csharp = new Keyword("C#");
Keyword dotnet = new Keyword(".NET");
Article LeadingEnd = new Article(fg, "前端", html, js);
Article DataBase = new Article(fg, "数据库", sql);
Article AfterEnd = new Article(fg, "后端", csharp, dotnet);
Article UI = new Article(xy, "UI", css);
LeadingEnd.Publish();
//Wait();
DataBase.Publish();
//Wait();
AfterEnd.Publish();
//Wait();
UI.Publish();
Comment comment1 = new Comment(pzq, "飞哥真帅", LeadingEnd);
Comment comment2 = new Comment(cy, "讲得好", AfterEnd);
Comment comment3 = new Comment(xlt, "沙区扛把子觉得你可以", DataBase);
Comment comment4 = new Comment(xlt, "这个好！这个好！", UI);
comment1.Publish();
comment2.Publish();
comment3.Publish();
comment4.Publish();
IEnumerable <Article> articles = new List <Article> {
LeadingEnd, DataBase, AfterEnd, UI
};
//找出“飞哥”发布的文章
var articleOfFg = from a in articles
where a.Author.Name == "飞哥"
select a;
var articleOfFgLam = articles.Where(a => a.Author.Name == "飞哥");
Console.WriteLine("飞哥发布的文章有如下：");
foreach (var item in articleOfFg)
{
Console.WriteLine(item.Title);
}
Console.WriteLine();
//找出2019年1月1日以后“小鱼”发布的文章
var articleTo190101OfXy = from a in articles
where a.PublishTime > new DateTime(2019 - 1 - 1) && a.Author.Name == "小余"
select a;
var articleTo190101OfXyLam = articles.Where(a => a.PublishTime > new DateTime(2019 - 1 - 1) && a.Author.Name == "小余");
Console.WriteLine("小余于2019-01-01之后发布的文章有如下：");
foreach (var item in articleTo190101OfXy)
{
Console.WriteLine(item.Title);
}
Console.WriteLine();
//foreach (var item in articleTo190101OfXyLam)
//{
// Console.WriteLine(item.Title);
//}
//按发布时间升序 / 降序排列显示文章
var articleOrderByTimeAsce = from a in articles
orderby a.PublishTime ascending
select a;
var articleOrderByTimeDesc = from a in articles
orderby a.PublishTime descending
select a;
var articleOrderByTimeAsceLam = articles.OrderBy(a => a.PublishTime);
var articleOrderByTimeDescLam = articles.OrderByDescending(a => a.PublishTime);
Console.WriteLine("按发布时间升序排列：");
foreach (var item in articleOrderByTimeAsce)
{
Console.WriteLine(item.Title);
Console.WriteLine(item.PublishTime);
}
Console.WriteLine();
//统计每个用户各发布了多少篇文章
var articleCount = from a in articles
group a by a.Author into ac
select new
{
name = ac.Key.Name,
count = ac.Count()
};
var articleCountLam = articles.GroupBy(a => a.Author)
.Select(ac => new
{
name = ac.Key.Name,
count = ac.Count()
});
Console.WriteLine("统计用户发布的文章：");
foreach (var item in articleCount)
{
Console.WriteLine(item.name + item.count);
}
Console.WriteLine();
//找出包含关键字“C#”或“.NET”的文章
var articleContainToCsharpOrDotnet = from a in articles
where a.Keywords.IndexOf(csharp) >= 0 || a.Keywords.IndexOf(dotnet) >= 0
select a;
var articleContainToCsharpOrDotnetLam = articles.Where(
a =>
a.Keywords.Contains(csharp) ||
a.Keywords.Contains(dotnet));
foreach (var item in articleContainToCsharpOrDotnet)
{
Console.WriteLine("包含关键字“C#”或“.NET”的文章：");
Console.WriteLine(item.Title);
}
Console.WriteLine();
//找出评论数量最多的文章，相同就取第一个
var articleOfCommentMost = from a in articles
orderby a.Comments.Count() ascending
select a;
Console.WriteLine("找出评论数量最多的文章：");
Console.WriteLine(articleOfCommentMost.First().Title);
Console.WriteLine();
//找出每个作者评论数最多的文章
var CommentMostOfAuthor = from a in articles
group a by a.Author into cm
select new
{
name = cm.Key.Name,
title = cm.OrderBy(c => c.Comments.Count()).First().Title
};
Console.WriteLine("找出每个作者评论数最多的文章：");
foreach (var item in CommentMostOfAuthor)
{
Console.WriteLine(item.name + item.title);
}
Console.WriteLine();
//找出每个作者最近发布的一篇文章
var FinallyArticle = from a in articles
group a by a.Author into ga
select new
{
author = ga.Key.Name,
title = ga.OrderByDescending(a => a.PublishTime).First().Title
};
Console.WriteLine("找出每个作者最近发布的一篇文章：");
foreach (var item in FinallyArticle)
{
Console.WriteLine(item.author + item.title);
}
Problem problem1 = new Problem("标题1", fg, 19);
Problem problem2 = new Problem("标题2", fg);
Problem problem3 = new Problem("标题2", xlt, 20);
ContentService.Publish(problem1);
ContentService.Publish(problem2);
ContentService.Publish(problem3);
IList <Problem> problems = new List <Problem>()
{
problem1, problem2, problem3
};
//找出每一篇求助的悬赏都大于5个帮帮币的文章作者
var highPrice = problems.GroupBy(gp => gp.Author)
.Where(p => p.Min(r => r.Reward) > 5)
.Select(a => a.Key.Name);
foreach (var item in highPrice)
{
Console.WriteLine(item);
}
}