public T Add(T entity)
{
var result = dbContext.Set <T>().Add(entity);
dbContext.SaveChanges();
return(result);
}
public ActionResult Create(Article a)
{
if (ModelState.IsValid) //如果数据符合要求 （ 按照规则校验）
{
db.Articles.Add(a);
db.SaveChanges();
}
return(RedirectToAction("index"));
}
public ActionResult Create([Bind(Include = "UserId,UserName,Password,Gender,Email,SecurityQuestion,SecurityAnswer,QQ,Tel,Address,PostCode,RegTime,LastLoginTime")] User user)
{
if (ModelState.IsValid)
{
db.Users.Add(user);
db.SaveChanges();
return(RedirectToAction("Index"));
}
return(View(user));
}
public ActionResult Create([Bind(Include = "CategoryId,CategoryName")] Category category)
{
if (ModelState.IsValid)
{
db.Categorys.Add(category);
db.SaveChanges();
return(RedirectToAction("Index"));
}
return(View(category));
}
public ActionResult Create([Bind(Include = "Id,Title,Producer,Date,Category,DEscription")] News news)
{
if (ModelState.IsValid)
{
db.News.Add(news);
db.SaveChanges();
return(RedirectToAction("Index"));
}
return(View(news));
}
public ActionResult Create([Bind(Include = "ID,Title,ReleaseDate,Text")] NewsViewModel newsViewModel)
{
if (ModelState.IsValid)
{
db.News.Add(newsViewModel);
db.SaveChanges();
return(RedirectToAction("Index"));
}
return(View(newsViewModel));
}
public ActionResult Create([Bind(Include = "Id,TimeStamp,Text")] NewsItem newsItem)
{
if (ModelState.IsValid)
{
db.News.Add(newsItem);
db.SaveChanges();
return(RedirectToAction("Index"));
}
return(View(newsItem));
}
static void Main()
{
var context = new NewsDBContext();
var newContext = new NewsDBContext();
var firstNews = context.News.FirstOrDefault();
Console.WriteLine("Application started");
Console.Write("Text from DB: ");
Console.WriteLine(firstNews.NewsContent);
Console.WriteLine("Enter the corrected text: ");
firstNews.NewsContent = Console.ReadLine();
try
{
context.SaveChanges();
Console.WriteLine("Changes successfully saved in the DB.");
}
catch (DbUpdateConcurrencyException ex)
{
var textFromDB = newContext.News.FirstOrDefault();
Console.WriteLine("Conflict! Text from DB: {0}. Enter the corrected text:", textFromDB.NewsContent);
Main();
}
}
static void Main()
{
var context = new NewsDBContext();
var data = context.News.Find(1);
//WARNING: Concurency handling should be tested by running two instances of the app.
while (true)
{
try
{
data.Content = Console.ReadLine();
context.SaveChanges();
Console.WriteLine("Changes successfully saved in the DB.");
break;
}
catch (DbUpdateConcurrencyException exc)
{
exc.Entries.Single().Reload();
Console.WriteLine("Conflict! Text from DB:" + context.News.Find(1).Content
+ ". Enter the corrected text:");
}
}
}
public static void Main()
{
using (var db = new NewsDBContext())
{
db.News.Add(new News { Content = "Some very long and interesting content!" });
db.SaveChanges();
}
}
public int Create(ECategories e)
{
int res = 0;
try
{
DataAccess.Models.Categories obj = new Categories();
obj.Name = e.Name;
obj.Description = e.Description;
db.Categories.Add(obj);
db.SaveChanges();
res = obj.IdCategory;
}
catch (Exception)
{
throw;
}
return(res);
}
private static void CatchConcurrencyConflict(NewsDBContext context, New loadedEntity)
{
Console.WriteLine("Text from DB: {0}", loadedEntity.Content);
Console.WriteLine("Enter the corrected text:");
string newEntity = Console.ReadLine();
loadedEntity.Content = newEntity;
try
{
context.SaveChanges();
Console.WriteLine("Changes successfully saved in the DB.");
}
catch (DbUpdateConcurrencyException)
{
Console.WriteLine("Conflict!");
context.Entry(loadedEntity).Reload();
CatchConcurrencyConflict(context, loadedEntity);
}
}
/// <summary>
/// Gets news and updates database records.
/// </summary>
/// <param name="url">target web URL.</param>
/// <param name="type">target web category.</param>
private void Update(string url, string type)
{
// Gets DbContext.
var builder = new DbContextOptionsBuilder <NewsDBContext>();
var options = builder.UseMySql(configuration.GetConnectionString("Default")).Options;
NewsDBContext context = new NewsDBContext(options);
var recordsSet = context.TblNews; // DbSet of DbContext.
HtmlDocument htmlDoc = GetHtmlDoc(url); // HTML Document.
// Get TAG nodes.
var nodes = htmlDoc.DocumentNode.SelectNodes(
"//div[@class = 'tabContents active']/table/tr");
// Get news contents.
if (nodes != null)
{
int index = 0;
foreach (var node in nodes)
{
if (index == 0)
{ // First node is table head, skip it.
index++;
continue;
}
var newsNode = node.Element("td").Element("a"); // News contents.
try
{ // If record is only one.
var record = recordsSet.Single(n => // Query a record that need update in set.
n.NewsRank == index && n.NewsType == type);
record.NewsUrl = newsNode.GetAttributeValue("href", null); // URL
var doc = GetHtmlDoc(record.NewsUrl);
var content = doc.DocumentNode.SelectSingleNode(
"//div[@class = 'post_content_main']");
var title = content.Element("h1").InnerText;
var text = content.SelectSingleNode(
"//div[@class = 'post_body']/div[@class = 'post_text']")
.SelectNodes("p");
string str = "";
foreach (var p in text)
{
str = str + "<p>" + p.InnerHtml + "</p>";
}
/* Get source.
* var source = content.SelectSingleNode("//div[@class = 'post_time_source']");
* source.RemoveChild(source.SelectSingleNode("//a[@class = 'post_jubao']"));
* Console.WriteLine(source.InnerText.Trim());
*/
record.NewsTitle = title; // Title.
record.NewsContent = str; // Content.
record.SubmitTime = DateTime.Now; // Submit time.
context.SaveChanges(); // save update.
}
catch (Exception)
{ // record is more or less than one.
break;
}
if (index == 10)
{
break; // Get only 10 pieces of news.
}
index++;
} // foreach (var node in nodes) ---
} // if (nodes != null) ---
else
{ // Getting nodes failed.
Console.WriteLine("ERROR!");
}
} // private void Update(string url, string type) ---
